v0.223.0: the app-down alarm reached nobody (R-329), and the stop nobody heard (R-386)

R-329. NotifyAppStartFailures emitted severity "warn". The hub accepts exactly
{info, warning, error, critical} and silently coerces anything else to "info",
which severityNotifies then drops BEFORE both legs. Banner shown, event stored,
POST 200, no mail sent. One word.

This is the second time: DiskAlertKind.Severity emitted "warn" until v0.215.0
and its own comment records that every warning-level disk alert went to nobody.
A comment recorded the lesson and nothing enforced it. The guard is now an AST
walk over the whole controller - grep cannot work here, since "warn" appears
legitimately nine times as a healthcheck status vocabulary.

The sweep found exactly one bad severity. Its limits are stated: the walk cannot
follow a variable, so all six dynamic call sites are registered by name with the
values each can take, and a new one fails the test. Two of the six were found by
the guard, not by the hand sweep before it.

Also pinned: fillwatch.Band.Severity() returns "" for BandOK, which would vanish
the same way. It is unreachable because Check() notifies only on escalation -
but that safety lives in a different function from the one that looks unsafe, so
the test asserts the consequence rather than the mapping.

app_start_failed gains a customer toggle, DEFAULT OFF, per operator ruling. The
operator is mailed either way: processOperator never consults customer prefs.
It is deliberately NOT in operatorOnlyEvents, which would make the toggle a lie.

R-386. classifyRunStates decided "the customer stopped this" from the STATE, so
every stopped stack was assumed deliberate. Measured on demo-hp: privatebin
stopped out of band, nine scans, zero events, zero banner - while the comment
beside it claimed an out-of-band stop still alerts.

DesiredState already records the answer and has exactly one writer. Stopped ->
no alarm; Running -> alarm; absent -> UNKNOWN, keep today's behaviour AND say
so. Absent stays silent deliberately: reading it as "nobody asked" would email
about every app anyone ever stopped, fleet-wide, on the first cycle after
upgrade. The gap is bounded not silent - IntentUnknown is set and the names are
logged at INFO on the heartbeat cadence. failedRestart still lifts a Stopped
intent, or F-CRIT-1 re-opens. No new DesiredState writer.

Two settings toggles each governed two alarms. "Lemez figyelmeztetes (90%+)"
also wrote disk_critical, the drive-is-FAILING alarm. Now four honest toggles;
12 became 15. A no-op save stores the existing slice verbatim, so byte identity
is by construction - without that guard the defaults case reorders, which the
red-proof caught.

Test count 1504 -> 1522. Five red-proofs, five seen failing; one passed first
time and is reported - that mutation was inert, not the test weak.

CHANGELOG.md

@@ -1,3 +1,104 @@
+## v0.223.0 — the alarm we had just built reached nobody, and the stop nobody heard (2026-08-23, R-329 + R-386)
+**MinAgent: 0.129.0** (unchanged — no new agent coupling)
+
+### R-329 — one word, and every `app_start_failed` was delivered to no one
+
+`NotifyAppStartFailures` emitted severity **`"warn"`**. The hub's vocabulary is exactly
+`{info, warning, error, critical}` and it **silently coerces** anything else to `info` at ingest;
+`severityNotifies` then drops `info`, returning **before both** the operator and the customer leg. So
+the banner appeared, the hub stored the event, the POST returned 200, and no mail left the building.
+
+**This is the SECOND time.** `DiskAlertKind.Severity` emitted `"warn"` until v0.215.0, and its own doc
+comment records that every Figyelmeztetés-level disk alert the product ever produced went to nobody.
+The lesson was written down. Nothing enforced it. It happened again — and it hid for months only
+because R-384's ordering defect meant the event could not fire at all, so a broken severity had
+nothing to break.
+
+**The guard is now an AST walk over the whole controller**
+(`TestR329_EveryEmittedSeverityIsInTheHubVocabulary`), not a comment and not a `strings.Contains`:
+the word "warn" appears legitimately nine times in `internal/monitor` and `internal/selftest` as a
+*healthcheck status*, and only one of those hits was the defect.
+
+**The sweep found exactly one bad severity and is reported in full**, including its limits. The walk
+cannot follow a variable, so the six call sites that pass one are **registered by name with the values
+each can take** — a new dynamic site fails the test rather than slipping past it. Two of those six
+were found by the guard itself, not by the hand sweep that preceded it.
+
+**A latent one, found while sweeping and pinned rather than left:** `fillwatch.Band.Severity()`
+returns `""` for `BandOK`, which would coerce to `info` and vanish. It is unreachable — `Check()`
+notifies only on an *escalation* — but that safety lives in a different function from the one that
+looks unsafe. `TestR329_FillwatchNeverEmitsTheEmptySeverity` pins the **consequence**, not the mapping.
+
+### R-329, part two — the app-down alarm gets a customer switch, DEFAULT OFF
+
+`app_start_failed` is now a customer-facing toggle („Alkalmazás nem fut"), and is **deliberately NOT
+in `DefaultEnabledEvents`** (operator ruling, 2026-08-23).
+
+**The operator is emailed either way.** `processOperator` consults only `operatorOn`, the address and
+a one-hour cooldown — never customer preferences. The toggle governs the customer leg alone. It is
+also deliberately **not** added to `operatorOnlyEvents`: that would make the switch visible,
+flickable and structurally incapable of delivering, which is worse than not offering it.
+
+### R-386 — ask the field that knows, instead of guessing from the state
+
+`classifyRunStates` decided "the customer stopped this" from `st.State == StateStopped`. **Every**
+stopped stack was therefore assumed deliberate. Measured live on `demo-hp` 2026-08-23: `privatebin`
+stopped out of band, nine dead-app scans over four minutes, **zero events and zero banner lines** —
+while the comment beside the code claimed an out-of-band stop *"still alerts"*.
+
+The product already records the answer. `DesiredState` is what the customer asked for, it has exactly
+**one writer** (their own action), and it is tri-state. The ruling, operator-approved:
+
+| Intent | Verdict |
+|---|---|
+| `Stopped` | the customer asked → **no alarm** (unchanged) |
+| `Running` | nobody asked → **ALARM** (the fix) |
+| absent | **UNKNOWN, never "running"** → no alarm, **and say so** |
+
+**The unknown case keeps today's behaviour deliberately.** Reading absent as "nobody asked" would, on
+the first cycle after upgrade, email about every app any owner has ever deliberately stopped —
+fleet-wide, from a field that predates the intent being asked of it. The backfill cannot help: it
+seeds `Running` only from an observed-UP reading, so anything stopped at upgrade time stays unknown —
+which is exactly the ambiguous population.
+
+**The gap is BOUNDED, not silent.** Every suppression sets `AppRunState.IntentUnknown`, and the
+scheduler logs the names at INFO on the heartbeat cadence, so an operator can answer *"how many apps
+am I blind to, and which?"*. **A rule without a mechanism is a wish** — the log line is the mechanism.
+It closes itself as apps are started and stopped through the interface.
+
+`failedRestart` still lifts a `Stopped` intent, and that ordering is load-bearing: removing it
+re-opens F-CRIT-1's indefinitely-silent dead app. Every existing suppression — quiesce grace, boot
+grace, crash-loop threshold, the `Deploying` skip — is untouched. **No new `DesiredState` writer was
+added**; the field keeps its single owner.
+
+### Two settings toggles secretly governed two alarms each
+
+„Lemez figyelmeztetés (90%+)" also wrote `disk_critical` — the drive-is-**failing** alarm. A customer
+silencing a disk-nearly-full notice silenced "this drive is dying", and the label claimed only the
+first. „Elvárt mentés elmaradt" had the same shape across the file-backup and database-dump misses.
+Each is now two honestly-labelled toggles; **12 toggles became 15.**
+
+**The risk was never the split, it was the migration.** Every stored list was written by the OLD form
+names. A no-op save now travels a different path, and a settings page that rewrites a setting while
+merely rendering it would be worse than the defect. So a save whose event **set** is unchanged stores
+the **existing slice verbatim** — byte-identity by construction, not by argument. The legacy compound
+form names are still read, so a stale browser tab cannot drop a key.
+
+**This was not theoretical:** with the guard removed, the `defaults` case reorders. The red-proof
+caught it.
+
+### Tests
+
+`internal/notify/r329_severity_contract_test.go`, `internal/fillwatch/r329_severity_test.go`,
+`cmd/controller/r386_intent_test.go`, `internal/web/r329_toggle_split_test.go`.
+Test count **1504 → 1522**.
+
+**Red-proofs: five planted, five seen failing — and ONE PASSED FIRST TIME AND IS REPORTED.** The
+fillwatch mutation `next <= prev` → `next < prev` is **inert**: an earlier `if next == prev { continue }`
+had already removed the equal case, so the code's behaviour did not change and the test was right to
+pass. Removing the de-escalation guard outright convicts it. **A red-proof that passes needs the
+mutation checked before either verdict is believed.**
+
 ## v0.222.0 — an app whose database dies raised no alarm, because the wrong question answered first (2026-08-23, R-384 + R-383)
 **MinAgent: 0.129.0** (unchanged — no new agent coupling)
 

controller/cmd/controller/main.go

@@ -732,6 +732,7 @@ func main() {
 		notifier.NotifyAppStartFailures(states)
 		deadAppScans++
 		noteDeadAppScan(logger, deadAppScans, len(states), len(dead))
+		noteUnknownIntentSuppressions(logger, states)
 		return nil
 	})
 
@@ -1731,6 +1732,36 @@ func noteDeadAppScan(logger *log.Logger, scans, evaluated, down int) {
 		scans, evaluated, down)
 }
 
+// noteUnknownIntentSuppressions reports every app whose dead-app alarm was suppressed ONLY because
+// no customer intent was ever recorded (R-386, §4's ruling).
+//
+// **A rule without a mechanism is not a rule.** §4 chose to keep today's behaviour for the unknown
+// case, which is the safe choice — but a safe choice that is invisible is indistinguishable from the
+// defect it replaced. This line is what makes the gap BOUNDED rather than silent: an operator can
+// grep one word and answer "how many apps am I blind to, and which?".
+//
+// It rides the same cadence as the F-OBS heartbeat rather than firing every 30 s, for the reason
+// noteDeadAppScan records: a per-scan line is 2880 lines/day of noise, and noise is what made the
+// original author choose silence. The population only changes when someone starts or stops an app.
+func noteUnknownIntentSuppressions(logger *log.Logger, states []notify.AppRunState) {
+	if logger == nil || deadAppHeartbeatEvery <= 0 || deadAppScans%deadAppHeartbeatEvery != 0 {
+		return
+	}
+	var names []string
+	for _, s := range states {
+		if s.IntentUnknown {
+			names = append(names, s.Name)
+		}
+	}
+	if len(names) == 0 {
+		return
+	}
+	sort.Strings(names)
+	logger.Printf("[INFO] [deadapp] %d stopped app(s) have NO recorded customer intent, so their "+
+		"dead-app alarm is suppressed by the unknown-intent fallback (R-386): %s. This closes itself "+
+		"as each app is started or stopped through the interface.", len(names), strings.Join(names, ", "))
+}
+
 // bootReconcileSettle is the delay before the FIRST observation. It lets the initial scan, the first
 // status refresh and the two crash recoveries land before the R-52 sweep decides what "down" means.
 var bootReconcileSettle = 5 * time.Second
@@ -2169,9 +2200,58 @@ func classifyRunStates(sts []stacks.Stack, quiesced map[string]bool, failedResta
 		// brief restart never reaches it and the two suppression windows compose into one bounded
 		// delay. Quiesce suppression below still wins inside its own window.
 		crashLooping := st.CrashLooping(now)
-		userStopped := st.State == stacks.StateStopped && !failedRestart[st.Name]
+
+		// R-386: ASK THE FIELD THAT KNOWS, do not guess from the state.
+		//
+		// Until v0.223.0 this read `st.State == StateStopped && !failedRestart[...]` — i.e. EVERY
+		// stopped stack was assumed to be a deliberate customer stop. Measured on `demo-hp`
+		// 2026-08-23: `privatebin` stopped out of band, nine dead-app scans, zero events, zero
+		// banner. The comment above claimed an out-of-band stop "still alerts"; it did not, because
+		// `aggregateState` folds StateExited into the stopped counter and StateExited never survives
+		// aggregation.
+		//
+		// `DesiredState` is what the customer actually asked for, it has exactly ONE writer (the
+		// customer's own action — see the field's comment in internal/stacks/deploy.go), and it is
+		// TRI-state. The three-way ruling, operator-approved 2026-08-23:
+		//
+		//   Stopped → the customer asked        → no alarm  (unchanged)
+		//   Running → nobody asked              → ALARM     (the R-386 fix)
+		//   absent  → UNKNOWN, never "running"  → no alarm, AND say so (see IntentUnknown)
+		//
+		// The absent case keeps today's behaviour deliberately. Reading unknown as "nobody asked"
+		// would, on the first cycle after this ships, email about every app any owner has ever
+		// deliberately stopped — fleet-wide, from a field that predates the intent it is being asked
+		// about. That is the same over-correction the tri-state exists to prevent, and the backfill
+		// cannot help: it seeds Running only from an observed-UP reading, so anything stopped at
+		// upgrade time stays unknown — which is exactly the ambiguous population.
+		//
+		// The gap is BOUNDED AND NAMED, not silent: IntentUnknown is set, the caller logs it at INFO
+		// with the app name, and an operator can therefore answer "how many apps am I blind to?".
+		// It closes itself as apps are started and stopped through the interface.
+		//
+		// `failedRestart` still lifts a Stopped intent, and that ordering is load-bearing: the
+		// quiesce loop stops stacks by the same path a customer does, so a stack it stopped and could
+		// NOT restart must alarm whatever the intent says. Removing that term re-opens F-CRIT-1's
+		// indefinitely-silent dead app.
+		intentUnknown := false
+		userStopped := false
+		if st.State == stacks.StateStopped && !failedRestart[st.Name] {
+			switch stacks.DesiredStateOf(st) {
+			case stacks.DesiredStateStopped:
+				userStopped = true
+			case stacks.DesiredStateRunning:
+				userStopped = false
+			default: // DesiredStateUnknown — the §4 fallback
+				userStopped = true
+				intentUnknown = true
+			}
+		}
+
 		down := (stacks.IsDownState(st.State) || crashLooping) && !userStopped && !quiesced[st.Name]
-		states = append(states, notify.AppRunState{Name: st.Name, DisplayName: st.Meta.DisplayName, Down: down})
+		states = append(states, notify.AppRunState{
+			Name: st.Name, DisplayName: st.Meta.DisplayName, Down: down,
+			IntentUnknown: intentUnknown && !down,
+		})
 		if down {
 			dead = append(dead, web.DeadApp{Name: st.Name, DisplayName: st.Meta.DisplayName, State: string(st.State)})
 		}

controller/cmd/controller/r386_intent_test.go

@@ -0,0 +1,270 @@
+package main
+
+import (
+	"bytes"
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"log"
+	"strings"
+	"testing"
+	"time"
+
+	"gitea.dooplex.hu/admin/felhom-controller/internal/notify"
+	"gitea.dooplex.hu/admin/felhom-controller/internal/stacks"
+)
+
+// R-386 — the dead-app classifier asked the STATE whether the customer wanted an app stopped, when
+// the product already records the ANSWER.
+//
+// THE DEFECT. `userStopped` was `st.State == StateStopped && !failedRestart[...]` — every stopped
+// stack was assumed to be a deliberate customer stop. Measured live on `demo-hp` 2026-08-23:
+// `privatebin` stopped out of band, nine dead-app scans over four minutes, **zero events and zero
+// banner lines**, against a positive control from the same box seventeen minutes earlier. The comment
+// beside the code claimed an out-of-band stop "still alerts". It did not.
+//
+// THE LAYER. These sit at `classifyRunStates`, which is the single derivation point for "this app is
+// down" and the only place the guess was made. `classifyRunStates` is pure, so the fixture is exact
+// rather than a race against docker.
+//
+// RED-PROOF (observed, see REPORT.md): restore the pre-fix predicate
+//
+//	userStopped := st.State == stacks.StateStopped && !failedRestart[st.Name]
+//
+// and TestR386_OutOfBandStopWithRunningIntentAlarms fails with `dead-app banner = [], want privatebin`
+// — which is exactly what the live box reported.
+
+func stoppedStack(name, intent string) stacks.Stack {
+	st := stacks.Stack{Name: name, Deployed: true, State: stacks.StateStopped}
+	if intent != stacks.DesiredStateUnknown {
+		st.AppConfig = &stacks.AppConfig{DesiredState: intent}
+	}
+	return st
+}
+
+// Scenario D — R-386's measured case. Intent says Running; something stopped it anyway.
+func TestR386_OutOfBandStopWithRunningIntentAlarms(t *testing.T) {
+	dead, states := classifyRunStates(
+		[]stacks.Stack{stoppedStack("privatebin", stacks.DesiredStateRunning)}, nil, nil, time.Now())
+
+	if len(dead) != 1 || dead[0].Name != "privatebin" {
+		t.Fatalf("dead-app banner = %+v, want exactly privatebin — nobody asked for this app to be "+
+			"stopped, so its being stopped is a fault (measured silent on demo-hp 2026-08-23)", dead)
+	}
+	if !states[0].Down {
+		t.Fatalf("run state = %+v, want Down=true (this is what NotifyAppStartFailures reads)", states[0])
+	}
+	if states[0].IntentUnknown {
+		t.Errorf("IntentUnknown set for an app with a RECORDED intent — the log line would name an " +
+			"app that is not actually ambiguous")
+	}
+}
+
+// Scenario C — the customer pressed Stop. Telling them their own action was a fault is the thing
+// v0.164.0 was written to stop, and R-386 must not undo it.
+func TestR386_CustomerStopStaysSilent(t *testing.T) {
+	dead, states := classifyRunStates(
+		[]stacks.Stack{stoppedStack("docmost", stacks.DesiredStateStopped)}, nil, nil, time.Now())
+
+	if len(dead) != 0 {
+		t.Fatalf("a customer's own Stop raised an alarm: %+v", dead)
+	}
+	if states[0].Down {
+		t.Fatalf("run state = %+v, want Down=false — the customer asked for this", states[0])
+	}
+	if states[0].IntentUnknown {
+		t.Errorf("IntentUnknown set for an app whose intent is RECORDED as stopped")
+	}
+}
+
+// Scenario E — intent absent. §4's ruling: keep today's behaviour, and SAY SO.
+func TestR386_AbsentIntentSuppressesButIsAnnounced(t *testing.T) {
+	dead, states := classifyRunStates(
+		[]stacks.Stack{stoppedStack("legacy-app", stacks.DesiredStateUnknown)}, nil, nil, time.Now())
+
+	if len(dead) != 0 {
+		t.Fatalf("an app with NO recorded intent alarmed: %+v — on the first cycle after upgrade "+
+			"that is every app any owner ever deliberately stopped, fleet-wide", dead)
+	}
+	if states[0].Down {
+		t.Fatalf("run state = %+v, want Down=false", states[0])
+	}
+	// THE HALF THAT MAKES THE GAP BOUNDED RATHER THAN SILENT.
+	if !states[0].IntentUnknown {
+		t.Fatalf("IntentUnknown = false — the suppression happened but nothing records it, so an " +
+			"operator cannot answer 'how many apps am I blind to?'. A rule without a mechanism is " +
+			"not a rule")
+	}
+}
+
+// And the log line itself — the mechanism §4 demands, asserted as an OBSERVABLE, not as "the
+// function ran". The heartbeat cadence is deliberate; drive the counter to a firing scan.
+func TestR386_UnknownIntentIsLoggedWithTheAppName(t *testing.T) {
+	var buf bytes.Buffer
+	logger := log.New(&buf, "", 0)
+
+	states := []notify.AppRunState{
+		{Name: "zulip", IntentUnknown: true},
+		{Name: "legacy-app", IntentUnknown: true},
+		{Name: "docmost"}, // recorded intent — must NOT appear
+	}
+
+	saved := deadAppScans
+	t.Cleanup(func() { deadAppScans = saved })
+
+	// A non-firing scan says nothing (the 2880-lines/day lesson).
+	deadAppScans = 1
+	noteUnknownIntentSuppressions(logger, states)
+	if buf.Len() != 0 {
+		t.Fatalf("logged on a non-heartbeat scan: %q", buf.String())
+	}
+
+	// A firing scan names every ambiguous app, and only those.
+	deadAppScans = deadAppHeartbeatEvery
+	noteUnknownIntentSuppressions(logger, states)
+	out := buf.String()
+	if !strings.Contains(out, "[INFO]") {
+		t.Errorf("not logged at INFO — it must survive a default logging.level box: %q", out)
+	}
+	for _, want := range []string{"zulip", "legacy-app", "2 stopped app(s)", "R-386"} {
+		if !strings.Contains(out, want) {
+			t.Errorf("log line %q does not contain %q", out, want)
+		}
+	}
+	if strings.Contains(out, "docmost") {
+		t.Errorf("log line names an app with a RECORDED intent: %q", out)
+	}
+
+	// Nothing ambiguous → nothing said.
+	buf.Reset()
+	noteUnknownIntentSuppressions(logger, []notify.AppRunState{{Name: "docmost"}})
+	if buf.Len() != 0 {
+		t.Errorf("logged with no ambiguous apps: %q", buf.String())
+	}
+}
+
+// Scenario F — F-CRIT-1 must not re-open. The quiesce loop stops stacks by the same path a customer
+// does, so a stack it stopped and could NOT restart must alarm WHATEVER the intent says — including
+// when the intent is `Stopped`, which is the case that would silently swallow it.
+func TestR386_FailedRestartStillLiftsAStoppedIntent(t *testing.T) {
+	for _, intent := range []string{
+		stacks.DesiredStateStopped, stacks.DesiredStateRunning, stacks.DesiredStateUnknown,
+	} {
+		name := intent
+		if name == "" {
+			name = "(absent)"
+		}
+		t.Run(name, func(t *testing.T) {
+			dead, states := classifyRunStates(
+				[]stacks.Stack{stoppedStack("bookstack", intent)},
+				nil, map[string]bool{"bookstack": true}, time.Now())
+
+			if len(dead) != 1 {
+				t.Fatalf("intent %q: a stack the quiesce loop stopped and FAILED to restart did not "+
+					"alarm — this is F-CRIT-1's indefinitely-silent dead app, back through R-386's "+
+					"door: %+v", intent, dead)
+			}
+			if !states[0].Down {
+				t.Fatalf("intent %q: run state = %+v, want Down=true", intent, states[0])
+			}
+		})
+	}
+}
+
+// The quiesce suppression is unchanged and still wins inside its own window, for every intent.
+func TestR386_QuiesceSuppressionIsUntouched(t *testing.T) {
+	for _, intent := range []string{stacks.DesiredStateRunning, stacks.DesiredStateStopped} {
+		dead, states := classifyRunStates(
+			[]stacks.Stack{stoppedStack("bookstack", intent)},
+			map[string]bool{"bookstack": true}, nil, time.Now())
+		if len(dead) != 0 || states[0].Down {
+			t.Fatalf("intent %q: a quiesced stack alarmed (%+v) — R-97b's exact defect: the customer "+
+				"told their app broke during an outage the backup caused", intent, dead)
+		}
+	}
+}
+
+// A NON-stopped down state is unaffected by intent. A `degraded` stack (R-384) alarms regardless —
+// intent only ever governed the StateStopped whitelist, and widening it would silence R-384.
+func TestR386_IntentDoesNotReachNonStoppedDownStates(t *testing.T) {
+	st := stacks.Stack{
+		Name: "bookstack", Deployed: true, State: stacks.StateDegraded,
+		AppConfig: &stacks.AppConfig{DesiredState: stacks.DesiredStateStopped},
+	}
+	dead, states := classifyRunStates([]stacks.Stack{st}, nil, nil, time.Now())
+	if len(dead) != 1 || !states[0].Down {
+		t.Fatalf("a degraded stack was silenced by a Stopped intent (%+v) — R-386 must not reach "+
+			"past the StateStopped whitelist, or it undoes R-384", dead)
+	}
+}
+
+// --- production wiring (§10) --------------------------------------------------------------------
+//
+// A correct classifier the scheduler does not call is R-106's defect. This walks the AST of
+// main.go and proves the real job wires BOTH halves: the classification and the announcement.
+func TestR386_TheSchedulerWiresBothHalves(t *testing.T) {
+	fset := token.NewFileSet()
+	f, err := parser.ParseFile(fset, "main.go", nil, 0)
+	if err != nil {
+		t.Fatalf("parse main.go: %v", err)
+	}
+
+	var scan, announce, desiredRead bool
+	ast.Inspect(f, func(n ast.Node) bool {
+		call, ok := n.(*ast.CallExpr)
+		if !ok {
+			return true
+		}
+		switch fn := call.Fun.(type) {
+		case *ast.Ident:
+			switch fn.Name {
+			case "scanDeployedAppRunStates":
+				scan = true
+			case "noteUnknownIntentSuppressions":
+				announce = true
+			}
+		case *ast.SelectorExpr:
+			// stacks.DesiredStateOf(st) — the intent read itself, inside classifyRunStates
+			if fn.Sel.Name == "DesiredStateOf" {
+				desiredRead = true
+			}
+		}
+		return true
+	})
+
+	if !scan {
+		t.Error("scanDeployedAppRunStates is never called from main.go — the detector is not wired")
+	}
+	if !announce {
+		t.Error("noteUnknownIntentSuppressions is never called from main.go — the unknown-intent gap " +
+			"is silent again, which is the half §4 required to make it bounded")
+	}
+	if !desiredRead {
+		t.Error("stacks.DesiredStateOf is never called from main.go — the classifier is back to " +
+			"guessing from the state (R-386)")
+	}
+}
+
+// THE FENCE (§12): DesiredState has exactly ONE writer — the customer's own action. This session
+// must not have added a second. Twelve of StopStack's fourteen callers are machines, so a writer in
+// the wrong place makes a nightly backup indistinguishable from the customer pressing Stop.
+func TestR386_NoNewDesiredStateWriterInMain(t *testing.T) {
+	fset := token.NewFileSet()
+	f, err := parser.ParseFile(fset, "main.go", nil, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	ast.Inspect(f, func(n ast.Node) bool {
+		call, ok := n.(*ast.CallExpr)
+		if !ok {
+			return true
+		}
+		if sel, ok := call.Fun.(*ast.SelectorExpr); ok && sel.Sel.Name == "SetDesiredState" {
+			t.Errorf("%s: SetDesiredState is called from main.go — the field has ONE writer, the "+
+				"customer's own action. Reading it is fine; writing it here is the fenced act",
+				fset.Position(call.Pos()))
+		}
+		return true
+	})
+	_ = strings.TrimSpace
+}

controller/internal/fillwatch/r329_severity_test.go

@@ -0,0 +1,77 @@
+package fillwatch
+
+import "testing"
+
+// R-329 — `Band.Severity()` returns "" for BandOK, and "" is NOT in the hub's vocabulary
+// {info, warning, error, critical}. The hub would coerce it to "info" and mail nobody.
+//
+// **This is safe today, and this test is what keeps it safe**, because the safety is not in
+// `Severity()` at all — it is in `Check()`: the notify seam fires ONLY on an escalation
+// (`if next <= prev { continue }`), and BandOK is the lowest band, so a notification can never carry
+// it. That is an invariant held in one function about the behaviour of another, which is precisely
+// the shape this project has shipped wrong nine times.
+//
+// THE LAYER. The first test pins the mapping (a unit fact). The second pins the CONSEQUENCE — that
+// no notification can carry a band whose severity is empty — because the mapping being right is not
+// what makes the product correct, and asserting only the mapping is case #9's mistake.
+//
+// RED-PROOF (observed, see REPORT.md): REMOVE the de-escalation `continue` block from Check() —
+// every band change then notifies, and TestR329_FillwatchNeverEmitsTheEmptySeverity fails with
+// `notified with band ok → severity "" (event type "")`.
+//
+// **A weaker mutation is INERT here, and it is worth knowing which:** changing `if next <= prev` to
+// `if next < prev` does nothing, because an earlier `if next == prev { continue }` already removed
+// the equal case. That mutation was tried first, the test passed, and the test was right to pass —
+// the code had not changed behaviour. **A red-proof that passes is not automatically a weak test;
+// check the mutation actually applied before believing either verdict.**
+func TestR329_BandSeverityMapping(t *testing.T) {
+	for _, tc := range []struct {
+		band Band
+		want string
+	}{
+		{BandWarning, "warning"},
+		{BandCritical, "critical"},
+	} {
+		if got := tc.band.Severity(); got != tc.want {
+			t.Errorf("Band(%v).Severity() = %q, want %q", tc.band, got, tc.want)
+		}
+	}
+	// Documented and deliberate: BandOK has no severity because it has no event. The next test is
+	// what proves that cannot leak.
+	if got := BandOK.Severity(); got != "" {
+		t.Errorf("BandOK.Severity() = %q — if this ever becomes a real severity, an all-clear starts "+
+			"emailing customers; change it deliberately, not by accident", got)
+	}
+}
+
+// The consequence: drive a real Watcher up and back down and assert that every notification carries
+// a severity the hub will actually route.
+func TestR329_FillwatchNeverEmitsTheEmptySeverity(t *testing.T) {
+	// Reuses the package's existing harness (REUSE.md §4) rather than inventing a second fixture.
+	h := newHarness(t, Target{Path: "/mnt/data", Label: "Adatok"})
+
+	// up to warning, up to critical, back down, back to ok — the full round trip, so a
+	// de-escalation notification would be caught if one ever started firing.
+	for _, pct := range []float64{50, 91, 97, 91, 50} {
+		h.set("/mnt/data", pct, 100-pct)
+		h.check(t)
+	}
+
+	if len(h.events) == 0 {
+		// Positive control: a test that observes nothing proves nothing. If the fixture stopped
+		// crossing bands this would pass forever while checking air.
+		t.Fatal("no notifications at all — the fixture never crossed a band, so this test is checking " +
+			"nothing; fix the fixture before trusting a green")
+	}
+	for _, e := range h.events {
+		if e.Band.Severity() == "" || e.Band.EventType() == "" {
+			t.Errorf("notified with band %v → severity %q (event type %q): the hub coerces an unknown "+
+				"severity to \"info\" and then drops it, so this alert would reach NOBODY",
+				e.Band, e.Band.Severity(), e.Band.EventType())
+		}
+		if !map[string]bool{"info": true, "warning": true, "error": true, "critical": true}[e.Band.Severity()] {
+			t.Errorf("notified with severity %q, outside the hub vocabulary", e.Band.Severity())
+		}
+	}
+	t.Logf("%d crossings notified, every one with a routable severity", len(h.events))
+}

controller/internal/notify/notifier.go

@@ -508,6 +508,14 @@ type AppRunState struct {
 	Name        string
 	DisplayName string
 	Down        bool
+	// IntentUnknown is set when this app is STOPPED and no customer intent was ever recorded, so the
+	// alarm was suppressed by the §4 fallback rather than by a decision anyone made (R-386).
+	//
+	// It rides here rather than being a third return value or a logger parameter so that the log line
+	// and the suppression come from the SAME computation — a separately-derived log is a second
+	// source of truth, and the two drift. `classifyRunStates` stays pure and its signature does not
+	// move, which is what lets its existing tests keep testing what they were written to test.
+	IntentUnknown bool
 }
 
 // NotifyAppStartFailures fires an `app_start_failed` hub event ONCE per running→down transition
@@ -543,7 +551,14 @@ func (n *Notifier) NotifyAppStartFailures(apps []AppRunState) {
 		if name == "" {
 			name = a.Name
 		}
-		n.emit("app_start_failed", "warn",
+		// R-329: "warning", NOT "warn". The hub's vocabulary is exactly
+		// {info, warning, error, critical} and it COERCES anything else to "info" at ingest, silently
+		// — after which severityNotifies drops it and NEITHER leg runs. See DiskAlertKind.Severity's
+		// doc comment, which records the same mistake shipping once before (v0.215.0). This one was
+		// worse: it was invisible for months because R-384's ordering defect meant the event could
+		// not fire at all, so a broken severity had nothing to break.
+		// Pinned by TestR329_EveryEmittedSeverityIsInTheHubVocabulary (AST walk over this package).
+		n.emit("app_start_failed", "warning",
 			fmt.Sprintf("Telepített alkalmazás nem fut: %s", name),
 			AppDetails{StackName: a.Name, DisplayName: a.DisplayName})
 	}

controller/internal/notify/r329_severity_contract_test.go

@@ -0,0 +1,212 @@
+package notify
+
+import (
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"io/fs"
+	"path/filepath"
+	"sort"
+	"strconv"
+	"strings"
+	"testing"
+)
+
+// R-329 — the hub's severity vocabulary, pinned by an AST walk over the WHOLE controller.
+//
+// THE DEFECT THIS EXISTS TO KILL. `NotifyAppStartFailures` emitted severity `"warn"`. The hub accepts
+// only {info, warning, error, critical} and **silently coerces** anything else to `info` at ingest,
+// after which `severityNotifies` drops it and NEITHER the operator nor the customer leg runs. So the
+// dashboard showed the app down, the hub stored the event, and no mail left the building.
+//
+// **This is the SECOND time.** `DiskAlertKind.Severity`'s own doc comment records that it emitted
+// `"warn"` until v0.215.0, and that every Figyelmeztetés-level disk alert the product ever produced
+// was delivered to nobody. A comment recorded the lesson; nothing enforced it; it happened again.
+// **A comment is not a guard** — this is the guard.
+//
+// THE LAYER. This sits at the EMITTER, which is where the defect lives: the hub's coercion is
+// deliberate and correct (a lost alarm is worse than a mis-routed one), so nothing downstream can
+// detect a bad word — by design, the bad word ceases to exist at the hub's front door. The only
+// place the mistake is still visible is where it is written.
+//
+// WHY AN AST WALK AND NOT grep. `strings.Contains` over source cannot tell an emitted severity from
+// the word "warn" in a comment, a healthcheck status vocabulary (`internal/monitor`,
+// `internal/selftest` both legitimately use "warn"), or a `case "warn":` in an unrelated switch. The
+// 2026-08-23 sweep found nine such hits and exactly one real defect.
+//
+// RED-PROOF (observed, see REPORT.md): put `"warn"` back at notifier.go's app_start_failed emit and
+// this fails naming the file, line, call and value.
+
+// hubSeverityVocabulary is the hub's set, verbatim. Sources, both named so a reader can check rather
+// than trust: felhom.eu/hub/internal/api/handler.go (the ingest switch) and
+// felhom.eu/hub/internal/notify/dispatcher.go (severityNotifies).
+var hubSeverityVocabulary = map[string]bool{
+	"info": true, "warning": true, "error": true, "critical": true,
+}
+
+// severityArg names the functions that take a hub severity, and which argument it is.
+var severityArg = map[string]int{
+	"emit":      1, // (eventType, severity, message, details)
+	"PushEvent": 1, // (eventType, severity, message, details)
+}
+
+// knownDynamicSeveritySites are the call sites that pass a VARIABLE rather than a literal, so this
+// walk cannot check their value. Each was traced by hand on 2026-08-23 and every reachable value was
+// in the vocabulary. **They are listed so that a NEW dynamic site cannot appear unnoticed** — the
+// honest limit of an AST check is that it cannot follow a variable, and an unlisted limit is not a
+// limit, it is a hole.
+var knownDynamicSeveritySites = map[string]string{
+	"internal/notify/notifier.go:emit":                     `pass-through of its own severity parameter to PushEvent — the value is checked at emit's CALLERS, above`,
+	"internal/notify/notifier.go:NotifyControllerUpdated":  `local var: "info", or "error" when the update failed`,
+	"internal/notify/notifier.go:NotifyDRCompleted":        `local var: "info", or "warning" when failCount > 0`,
+	"internal/notify/notifier.go:NotifyAgentChannelDown":   `internal/channelhealth's classifier — every severity literal in checker.go is "warning" or "error"`,
+	"internal/notify/notifier.go:NotifyDiskHealthDegraded": `DiskAlertKind.Severity() — pinned behaviourally by TestR329_DiskAlertSeveritiesStillSatisfyTheContract`,
+	"cmd/controller/main.go:main":                          `fillwatch.Band.Severity() in the SetNotify closure — pinned by TestR329_FillwatchNeverEmitsTheEmptySeverity`,
+}
+
+func walkControllerFiles(t *testing.T, fn func(path string, fset *token.FileSet, f *ast.File)) {
+	t.Helper()
+	root, err := filepath.Abs("../..") // the controller module root
+	if err != nil {
+		t.Fatal(err)
+	}
+	fset := token.NewFileSet()
+	err = filepath.WalkDir(root, func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if d.IsDir() {
+			if d.Name() == "vendor" || d.Name() == ".git" || d.Name() == "node_modules" {
+				return filepath.SkipDir
+			}
+			return nil
+		}
+		if !strings.HasSuffix(path, ".go") || strings.HasSuffix(path, "_test.go") {
+			return nil
+		}
+		f, perr := parser.ParseFile(fset, path, nil, parser.ParseComments)
+		if perr != nil {
+			return fmt.Errorf("parse %s: %w", path, perr)
+		}
+		rel, _ := filepath.Rel(root, path)
+		fn(rel, fset, f)
+		return nil
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+// calleeName returns the bare function name for `foo(...)` and `x.foo(...)`.
+func calleeName(call *ast.CallExpr) string {
+	switch fn := call.Fun.(type) {
+	case *ast.Ident:
+		return fn.Name
+	case *ast.SelectorExpr:
+		return fn.Sel.Name
+	}
+	return ""
+}
+
+func TestR329_EveryEmittedSeverityIsInTheHubVocabulary(t *testing.T) {
+	var checked int
+	var dynamic []string
+
+	walkControllerFiles(t, func(rel string, fset *token.FileSet, f *ast.File) {
+		// Attribute each call to the FuncDecl that encloses it, by walking declarations rather than
+		// trusting Inspect's visit order — a closure inside main() must read as "main", and a call in
+		// a var block must not inherit the previous function's name.
+		for _, decl := range f.Decls {
+			fd, isFunc := decl.(*ast.FuncDecl)
+			enclosing := "(file scope)"
+			var scope ast.Node = decl
+			if isFunc {
+				enclosing = fd.Name.Name
+				scope = fd
+			}
+			inspectForSeverity(t, rel, enclosing, scope, fset, &checked, &dynamic)
+		}
+	})
+
+	// The walk must actually have found call sites — a guard that silently examines nothing is the
+	// "instrument that can drop results" failure, and it would pass forever.
+	if checked < 15 {
+		t.Fatalf("only %d severity literals examined — the AST walk is not reaching the call sites; "+
+			"fix this test before trusting a green from it", checked)
+	}
+	t.Logf("checked %d severity literals across the controller", checked)
+
+	// The dynamic sites are a stated limit, and the list is the mechanism that keeps it stated.
+	sort.Strings(dynamic)
+	seen := map[string]bool{}
+	for _, d := range dynamic {
+		if seen[d] {
+			continue
+		}
+		seen[d] = true
+		if _, known := knownDynamicSeveritySites[d]; !known {
+			t.Errorf("NEW dynamic severity call site %q — this walk cannot check a variable's value. "+
+				"Trace every value it can take; if all are in the hub vocabulary, add it to "+
+				"knownDynamicSeveritySites with the reason. Do not delete this check.", d)
+		}
+	}
+	for known := range knownDynamicSeveritySites {
+		if !seen[known] {
+			t.Errorf("registered dynamic site %q no longer exists — remove it from "+
+				"knownDynamicSeveritySites so the register stays honest", known)
+		}
+	}
+}
+
+// The vocabulary itself must match the hub's, and DiskAlertKind.Severity — the function whose doc
+// comment records the first occurrence — must still satisfy it.
+func TestR329_DiskAlertSeveritiesStillSatisfyTheContract(t *testing.T) {
+	for _, k := range []DiskAlertKind{
+		DiskAlertWarn, DiskAlertFailSelfReported, DiskAlertFailSectors,
+		DiskAlertFailTemperature, DiskAlertFailWorsened,
+	} {
+		if got := k.Severity(); !hubSeverityVocabulary[got] {
+			t.Errorf("DiskAlertKind(%d).Severity() = %q, not in the hub vocabulary", k, got)
+		}
+	}
+	// And the one that regressed: a warning must be a *warning*, not "warn" and not "info".
+	if got := DiskAlertWarn.Severity(); got != "warning" {
+		t.Errorf("DiskAlertWarn.Severity() = %q, want \"warning\"", got)
+	}
+}
+
+// inspectForSeverity checks every severity-taking call inside one declaration.
+func inspectForSeverity(t *testing.T, rel, enclosing string, scope ast.Node, fset *token.FileSet, checked *int, dynamic *[]string) {
+	t.Helper()
+	ast.Inspect(scope, func(n ast.Node) bool {
+		call, ok := n.(*ast.CallExpr)
+		if !ok {
+			return true
+		}
+		idx, wanted := severityArg[calleeName(call)]
+		if !wanted || len(call.Args) <= idx {
+			return true
+		}
+		lit, isLit := call.Args[idx].(*ast.BasicLit)
+		if !isLit || lit.Kind != token.STRING {
+			*dynamic = append(*dynamic, rel+":"+enclosing)
+			return true
+		}
+		val, err := strconv.Unquote(lit.Value)
+		if err != nil {
+			t.Errorf("%s: unparseable severity literal %s", fset.Position(lit.Pos()), lit.Value)
+			return true
+		}
+		*checked++
+		if !hubSeverityVocabulary[val] {
+			t.Errorf("%s: %s(...) emits severity %q, which is NOT in the hub's vocabulary "+
+				"{info, warning, error, critical}.\n"+
+				"    The hub COERCES it to \"info\" at ingest, SILENTLY, and severityNotifies then "+
+				"drops \"info\" — so this event is stored and emailed to NOBODY, on either leg.\n"+
+				"    This exact mistake shipped once before (DiskAlertKind.Severity, fixed v0.215.0).",
+				fset.Position(lit.Pos()), calleeName(call), val)
+		}
+		return true
+	})
+}

controller/internal/web/handlers.go

@@ -2016,6 +2016,50 @@ func (s *Server) settingsPasswordHandler(w http.ResponseWriter, r *http.Request)
 	http.Redirect(w, r, "/login?flash="+flash, http.StatusFound)
 }
 
+// sameEventSet reports whether two event lists hold the same keys, ignoring order and duplicates.
+// Used ONLY to decide whether a save is a no-op; never to decide what to store.
+func sameEventSet(a, b []string) bool {
+	if len(a) == 0 && len(b) == 0 {
+		return true
+	}
+	sa, sb := make(map[string]bool, len(a)), make(map[string]bool, len(b))
+	for _, e := range a {
+		sa[e] = true
+	}
+	for _, e := range b {
+		sb[e] = true
+	}
+	if len(sa) != len(sb) {
+		return false
+	}
+	for e := range sa {
+		if !sb[e] {
+			return false
+		}
+	}
+	return true
+}
+
+// dedupeEvents removes duplicates while PRESERVING ORDER.
+//
+// Order is not cosmetic here: the stored list is compared byte-for-byte by
+// TestR329Part4_RoundTripIsByteIdentical, which exists because a settings page that quietly reorders
+// or drops a key while merely RENDERING it would be a worse fault than the compound toggles it
+// replaced. It is needed because the legacy compound form name and its two replacements can both be
+// present in one POST — a browser still showing the old page, or a client that sends both.
+func dedupeEvents(in []string) []string {
+	seen := make(map[string]bool, len(in))
+	out := in[:0:0]
+	for _, e := range in {
+		if seen[e] {
+			continue
+		}
+		seen[e] = true
+		out = append(out, e)
+	}
+	return out
+}
+
 func (s *Server) settingsNotificationsHandler(w http.ResponseWriter, r *http.Request) {
 	_ = r.ParseForm()
 
@@ -2045,18 +2089,59 @@ func (s *Server) settingsNotificationsHandler(w http.ResponseWriter, r *http.Req
 		"backup_failed", "db_dump_failed", "backup_integrity_failed",
 		"crossdrive_failed", "offbox_enlarge_blocked", "storage_disconnected",
 		"node_down", "health_critical",
+		// R-329: app_start_failed is customer-switchable but DEFAULT OFF — it is deliberately absent
+		// from settings.DefaultEnabledEvents (operator ruling, 2026-08-23). The OPERATOR is emailed
+		// regardless: processOperator consults operatorOn, the address and a cooldown, and never the
+		// customer's preferences. This toggle governs the customer leg only.
+		"app_start_failed",
 		"storage_reconnected", "health_recovered",
 	} {
 		if r.FormValue("event_"+evt) == "on" {
 			enabledEvents = append(enabledEvents, evt)
 		}
 	}
-	// Compound toggles: one checkbox → two event types
+	// R-329 Part 4 — WAS: two compound toggles, one checkbox writing TWO event types each.
-	if r.FormValue("event_disk_alerts") == "on" {
+	//
-		enabledEvents = append(enabledEvents, "disk_warning", "disk_critical")
+	// `event_disk_alerts` labelled "Lemez figyelmeztetés (90%+)" also governed `disk_critical` — the
+	// drive-is-FAILING alarm. A customer switching off a disk-nearly-full notice silently switched off
+	// "this drive is dying", and the label claimed only the first. Those are not the same decision.
+	// `event_expected_missed` had the same shape over the backup and database-dump misses.
+	//
+	// Each is now its own labelled toggle. **The compound form names are still READ**, so a browser
+	// still on the old page, or a bookmarked POST, keeps working and cannot silently drop a key — the
+	// migration risk here is a settings page that changes a setting while rendering it, which would be
+	// worse than the defect. Pinned by TestR329Part4_RoundTripIsByteIdentical.
+	for _, c := range []struct {
+		form   string
+		events []string
+	}{
+		{"event_disk_alerts", []string{"disk_warning", "disk_critical"}}, // legacy compound
+		{"event_disk_warning", []string{"disk_warning"}},
+		{"event_disk_critical", []string{"disk_critical"}},
+		{"event_expected_missed", []string{"expected_backup_missed", "expected_dbdump_missed"}}, // legacy compound
+		{"event_expected_backup_missed", []string{"expected_backup_missed"}},
+		{"event_expected_dbdump_missed", []string{"expected_dbdump_missed"}},
+	} {
+		if r.FormValue(c.form) == "on" {
+			enabledEvents = append(enabledEvents, c.events...)
 		}
-	if r.FormValue("event_expected_missed") == "on" {
+	}
-		enabledEvents = append(enabledEvents, "expected_backup_missed", "expected_dbdump_missed")
+	enabledEvents = dedupeEvents(enabledEvents)
+
+	// R-329 Part 4 — A SAVE THAT CHANGES NOTHING MUST STORE NOTHING NEW.
+	//
+	// Splitting the two compound toggles rewrote which form names produce which event keys, so a
+	// customer who merely OPENS this page and presses Save now travels a different code path than the
+	// one that wrote their stored list. If that path emits the same SET in a different ORDER, their
+	// stored bytes change for no reason a person asked for — and a settings page that quietly rewrites
+	// a setting while rendering it is a worse fault than the compound labels being fixed.
+	//
+	// So: if the submitted set is identical to what is already stored, keep the STORED slice verbatim.
+	// This is byte-identity by construction rather than by argument, which is the only kind worth
+	// having here. Pinned by TestR329Part4_RoundTripIsByteIdentical over both starting shapes.
+	if cur := s.settings.GetNotificationPrefs(); cur != nil &&
+		sameEventSet(cur.EnabledEvents, enabledEvents) {
+		enabledEvents = cur.EnabledEvents
 	}
 
 	// EMPTY-EMAIL WIPE GUARD (2026-07-15 demo incident): a blank email box saved while events are

controller/internal/web/r329_toggle_split_test.go

@@ -0,0 +1,222 @@
+package web
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"reflect"
+	"regexp"
+	"strings"
+	"testing"
+
+	"gitea.dooplex.hu/admin/felhom-controller/internal/settings"
+)
+
+// R-329 Part 4 — two settings checkboxes each governed TWO alarms, and said so in neither label.
+//
+// `event_disk_alerts`, labelled „Lemez figyelmeztetés (90%+)", also wrote `disk_critical` — the
+// drive-is-FAILING alarm. A customer turning off a disk-nearly-full notice silently turned off "this
+// drive is dying". `event_expected_missed` had the same shape across the file-backup and
+// database-dump misses.
+//
+// THE RISK IS NOT THE SPLIT, IT IS THE MIGRATION. Every existing customer's stored list was written
+// by the OLD form names. After the split they render through new ones, so a customer who merely opens
+// the page and presses Save travels a different code path than the one that wrote their settings.
+// **A settings page that quietly changes a setting while rendering it is worse than the defect being
+// fixed**, so the round trip below is the real subject of this file.
+//
+// THE LAYER. This drives the REAL render (`settingsNotificationsPageHandler`) and the REAL save
+// (`settingsNotificationsHandler`) over a REAL temp-file `Settings`, and compares the STORED slice.
+// A test that only checked the handler's parsing would miss the half that matters: what the template
+// actually ticks.
+//
+// RED-PROOF (observed, see REPORT.md): drop the `sameEventSet` no-op guard in the save handler and
+// TestR329Part4_RoundTripIsByteIdentical/defaults fails, showing the stored order rewritten.
+
+// checkedBoxes renders the settings page and returns the form names the template ticked — i.e.
+// exactly what a browser would POST if the customer pressed Save without touching anything.
+func checkedBoxes(t *testing.T, s *Server) url.Values {
+	t.Helper()
+	req := httptest.NewRequest(http.MethodGet, "/settings/notifications", nil)
+	rr := httptest.NewRecorder()
+	s.settingsNotificationsPageHandler(rr, req)
+	if rr.Code != http.StatusOK {
+		t.Fatalf("render: HTTP %d", rr.Code)
+	}
+	body := rr.Body.String()
+	if !strings.Contains(body, "event_backup_failed") {
+		t.Fatalf("the notifications form did not render — this test would then prove nothing")
+	}
+
+	// <input type="checkbox" name="event_x" ... checked>  — `checked` before the closing angle.
+	re := regexp.MustCompile(`<input type="checkbox" name="(event_[a-z_]+)"([^>]*)>`)
+	out := url.Values{}
+	for _, m := range re.FindAllStringSubmatch(body, -1) {
+		if strings.Contains(m[2], "checked") {
+			out.Set(m[1], "on")
+		}
+	}
+	return out
+}
+
+func TestR329Part4_RoundTripIsByteIdentical(t *testing.T) {
+	cases := []struct {
+		name   string
+		stored []string
+	}{
+		{
+			// SHAPE 1: the default list every provisioned customer starts with — it contains BOTH
+			// halves of BOTH compounds, and in an order that is NOT the save handler's order.
+			name:   "defaults",
+			stored: append([]string(nil), settings.DefaultEnabledEvents...),
+		},
+		{
+			// SHAPE 2: a customer who switched the compounds OFF — neither key present.
+			name:   "compounds off",
+			stored: []string{"backup_failed", "node_down", "health_critical"},
+		},
+		{
+			// SHAPE 3: written by the OLD handler, so the compound pairs sit in its exact order.
+			name: "as the old handler wrote it",
+			stored: []string{
+				"backup_failed", "db_dump_failed", "storage_disconnected", "node_down",
+				"health_critical", "storage_reconnected",
+				"disk_warning", "disk_critical", "expected_backup_missed", "expected_dbdump_missed",
+			},
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			s, sett := notifyGuardServer(t)
+			if err := sett.SetNotificationPrefs(&settings.NotificationPrefs{
+				Email: "seed@felhom.eu", EnabledEvents: tc.stored, CooldownHours: 6,
+			}); err != nil {
+				t.Fatal(err)
+			}
+			before := append([]string(nil), sett.GetNotificationPrefs().EnabledEvents...)
+
+			// Render, take exactly what the template ticked, post it back unchanged.
+			form := checkedBoxes(t, s)
+			if len(form) == 0 && len(tc.stored) > 0 {
+				t.Fatalf("the template ticked NOTHING for a customer with %d stored events — the "+
+					"round trip would trivially 'pass' while silently wiping every setting", len(tc.stored))
+			}
+			form.Set("notification_email", "seed@felhom.eu")
+			form.Set("cooldown_hours", "6")
+
+			rr := postNotifications(t, s, form)
+			if rr.Code >= 400 {
+				t.Fatalf("save: HTTP %d", rr.Code)
+			}
+
+			after := sett.GetNotificationPrefs().EnabledEvents
+			if !reflect.DeepEqual(before, after) {
+				t.Errorf("a no-op save CHANGED the stored settings.\n  before: %v\n  after:  %v\n"+
+					"A settings page must not rewrite a setting while merely rendering it.", before, after)
+			}
+		})
+	}
+}
+
+// The split itself: each half is now independently switchable. The whole point is that turning off
+// "disk nearly full" must NOT turn off "disk failing".
+func TestR329Part4_TheTwoDiskAlarmsAreIndependent(t *testing.T) {
+	s, sett := notifyGuardServer(t)
+
+	// Only the FAILING alarm on — the mild one off.
+	rr := postNotifications(t, s, url.Values{
+		"notification_email":  {"a@b.hu"},
+		"cooldown_hours":      {"6"},
+		"event_disk_critical": {"on"},
+	})
+	if rr.Code >= 400 {
+		t.Fatalf("save: HTTP %d", rr.Code)
+	}
+	got := sett.GetNotificationPrefs().EnabledEvents
+	if !reflect.DeepEqual(got, []string{"disk_critical"}) {
+		t.Fatalf("enabled = %v, want exactly [disk_critical] — a customer must be able to keep the "+
+			"drive-is-failing alarm while silencing the 90%%-full notice", got)
+	}
+
+	// And the mirror: the mild one on, the failing one off.
+	rr = postNotifications(t, s, url.Values{
+		"notification_email": {"a@b.hu"},
+		"cooldown_hours":     {"6"},
+		"event_disk_warning": {"on"},
+	})
+	if rr.Code >= 400 {
+		t.Fatalf("save: HTTP %d", rr.Code)
+	}
+	if got := sett.GetNotificationPrefs().EnabledEvents; !reflect.DeepEqual(got, []string{"disk_warning"}) {
+		t.Fatalf("enabled = %v, want exactly [disk_warning]", got)
+	}
+}
+
+// The legacy compound form names must still be honoured — a browser left open on the old page, or a
+// bookmarked POST, must not silently drop a key.
+func TestR329Part4_LegacyCompoundNamesStillWork(t *testing.T) {
+	s, sett := notifyGuardServer(t)
+	rr := postNotifications(t, s, url.Values{
+		"notification_email":    {"a@b.hu"},
+		"cooldown_hours":        {"6"},
+		"event_disk_alerts":     {"on"},
+		"event_expected_missed": {"on"},
+	})
+	if rr.Code >= 400 {
+		t.Fatalf("save: HTTP %d", rr.Code)
+	}
+	got := sett.GetNotificationPrefs().EnabledEvents
+	want := []string{"disk_warning", "disk_critical", "expected_backup_missed", "expected_dbdump_missed"}
+	if !reflect.DeepEqual(got, want) {
+		t.Fatalf("legacy compound POST stored %v, want %v", got, want)
+	}
+}
+
+// Both the legacy compound AND its replacement in one POST must not double-write a key.
+func TestR329Part4_LegacyAndNewTogetherDoNotDuplicate(t *testing.T) {
+	s, sett := notifyGuardServer(t)
+	rr := postNotifications(t, s, url.Values{
+		"notification_email":  {"a@b.hu"},
+		"cooldown_hours":      {"6"},
+		"event_disk_alerts":   {"on"},
+		"event_disk_warning":  {"on"},
+		"event_disk_critical": {"on"},
+	})
+	if rr.Code >= 400 {
+		t.Fatalf("save: HTTP %d", rr.Code)
+	}
+	got := sett.GetNotificationPrefs().EnabledEvents
+	if !reflect.DeepEqual(got, []string{"disk_warning", "disk_critical"}) {
+		t.Fatalf("stored %v — a duplicated key would be pushed to the hub and re-render oddly", got)
+	}
+}
+
+// R-329 Part 1.3: the app-down toggle exists, is switchable, and is OFF by default.
+func TestR329_AppStartFailedToggleExistsAndDefaultsOff(t *testing.T) {
+	for _, e := range settings.DefaultEnabledEvents {
+		if e == "app_start_failed" {
+			t.Fatalf("app_start_failed is in DefaultEnabledEvents — the operator ruled it OFF by " +
+				"default; the OPERATOR is emailed regardless, via processOperator, which never " +
+				"consults customer preferences")
+		}
+	}
+
+	s, sett := notifyGuardServer(t)
+	// Default render must not tick it.
+	if _, ticked := checkedBoxes(t, s)["event_app_start_failed"]; ticked {
+		t.Errorf("the app-down toggle renders as ON for a fresh customer")
+	}
+	// And it must actually be switchable.
+	rr := postNotifications(t, s, url.Values{
+		"notification_email":     {"a@b.hu"},
+		"cooldown_hours":         {"6"},
+		"event_app_start_failed": {"on"},
+	})
+	if rr.Code >= 400 {
+		t.Fatalf("save: HTTP %d", rr.Code)
+	}
+	if got := sett.GetNotificationPrefs().EnabledEvents; !reflect.DeepEqual(got, []string{"app_start_failed"}) {
+		t.Fatalf("enabled = %v, want [app_start_failed] — a visible toggle that stores nothing is a lie", got)
+	}
+}

controller/internal/web/templates/settings_notifications.html

@@ -43,8 +43,12 @@
                         <span class="toggle-label">Távoli mentés — tárhelykeret-figyelmeztetés</span>
                     </label>
                     <label class="toggle">
-                        <input type="checkbox" name="event_disk_alerts" {{with .NotificationPrefs}}{{range .EnabledEvents}}{{if eq . "disk_warning"}}checked{{end}}{{end}}{{end}}>
+                        <input type="checkbox" name="event_disk_warning" {{with .NotificationPrefs}}{{range .EnabledEvents}}{{if eq . "disk_warning"}}checked{{end}}{{end}}{{end}}>
-                        <span class="toggle-label">Lemez figyelmeztetés (90%+)</span>
+                        <span class="toggle-label">Lemez betelőben (90% felett)</span>
+                    </label>
+                    <label class="toggle">
+                        <input type="checkbox" name="event_disk_critical" {{with .NotificationPrefs}}{{range .EnabledEvents}}{{if eq . "disk_critical"}}checked{{end}}{{end}}{{end}}>
+                        <span class="toggle-label">Lemez megtelt vagy meghibásodott</span>
                     </label>
                     <label class="toggle">
                         <input type="checkbox" name="event_storage_disconnected" {{with .NotificationPrefs}}{{range .EnabledEvents}}{{if eq . "storage_disconnected"}}checked{{end}}{{end}}{{end}}>
@@ -59,8 +63,16 @@
                         <span class="toggle-label">Rendszer állapot kritikus</span>
                     </label>
                     <label class="toggle">
-                        <input type="checkbox" name="event_expected_missed" {{with .NotificationPrefs}}{{range .EnabledEvents}}{{if eq . "expected_backup_missed"}}checked{{end}}{{end}}{{end}}>
+                        <input type="checkbox" name="event_expected_backup_missed" {{with .NotificationPrefs}}{{range .EnabledEvents}}{{if eq . "expected_backup_missed"}}checked{{end}}{{end}}{{end}}>
-                        <span class="toggle-label">Elvárt mentés elmaradt</span>
+                        <span class="toggle-label">Elvárt fájlmentés elmaradt</span>
+                    </label>
+                    <label class="toggle">
+                        <input type="checkbox" name="event_expected_dbdump_missed" {{with .NotificationPrefs}}{{range .EnabledEvents}}{{if eq . "expected_dbdump_missed"}}checked{{end}}{{end}}{{end}}>
+                        <span class="toggle-label">Elvárt adatbázismentés elmaradt</span>
+                    </label>
+                    <label class="toggle">
+                        <input type="checkbox" name="event_app_start_failed" {{with .NotificationPrefs}}{{range .EnabledEvents}}{{if eq . "app_start_failed"}}checked{{end}}{{end}}{{end}}>
+                        <span class="toggle-label">Alkalmazás nem fut</span>
                     </label>
                 </div>
             </div>