docs(reuse): register the v0.147.x helpers, patterns and seams

offsiteRestoreRootFor as THE home for backups/offsite-restore (it was open-coded
in three places). Two patterns: the detached-job+poll shape, now noting that FIVE
of them exist and agree on nothing so a sixth should extend rather than clone;
and streaming subprocess progress, which encodes the two traps tonight found —
a source reporting nothing is normal, and progress may only update on unit
completion, so degrade rather than fake a percentage. Seams: sambaImgFn and
offboxStreamRunner.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Nn3VgQk9iwEGgyx6QJ2NvE

REUSE.md

@@ -17,6 +17,7 @@
 | `UserdataDir` / `EnsureUserdataSkeleton` / `EnsureDirOwned` | controller/internal/appbackup/userdata.go | `(nsRoot)` / `(path, gid int)` | userdata/ tree w/ 2775 setgid gid-1000 convention | Linux-only chown via build-tag twin userdata_linux.go |
 | `HumanizeBytes` | controller/internal/appbackup/appdata.go | `(b int64) string` | Human byte sizes | Exported canonical; private clones exist (§6) |
 | `stablePathForName` / `agentWhere` | controller/internal/web/intermediary.go | `(name/registeredPath) string` | Map registry stable path `/mnt/felhom-drives/<n>` ↔ raw agent mount | Registry stores STABLE path; agent ops take the RAW mount — always convert |
+| `offsiteRestoreRootFor` | controller/internal/backup/offbox_verify_copies.go | `(drivePath string) string` | THE only place `backups/offsite-restore` is spelled | `offboxRestoreScratchDir` builds on it — the listing/delete surface MUST resolve byte-identical paths to what the restore wrote. Do not re-hardcode the segments (they were open-coded in 3 places before v0.147.0) |
 | `ProtectedHDDPaths` | controller/internal/stacks/delete.go | `(hddPath string) map[string]bool` | Never-delete set (root, appdata, backups, media, legacy felhom-data) | Consult before ANY recursive delete under a drive |
 
 ### Subprocess + timeout + exit-code discipline
@@ -173,6 +174,8 @@
 | Platform split | controller/internal/system/mounts_linux.go + mounts_other.go | `_linux.go`/`_other.go` twins; other = permissive no-op stubs for dev on Windows |
 | Debounced trigger + status (REFUSE-style — a too-soon fire is refused/lost) | controller/internal/sync/sync.go | `TriggerSync` 30s debounce, `Status()` snapshot struct, post-sync hook fan-out |
 | Coalescing trigger (trailing edge — a burst collapses but the LAST state always fires) | controller/internal/report/trigger.go | buffered-1 chan + non-blocking `Fire()` + single worker (quiet window → drain → min-interval → fire once); shape from hub `wgsync/reconciler.go` |
+| Detached job + status poll (single-flight, phase strings) | controller/internal/web/storage_init_job.go | acquire/release/set/**deep-copied** snapshot; phases mapped to Hungarian in the template; 1–3 s poll; terminal state **PROBED, not inferred**. Clones: `netstorage_job.go`, `samba_ensure_job.go` (v0.147.0). **Five of these now exist and agree on nothing — R-45 will unify them; prefer extending an existing one over a sixth** |
+| Streaming subprocess progress | controller/internal/backup/offbox_progress.go | `offboxStreamRunner` seam (stdout scanned line-by-line, stderr buffered, output tail-bounded) + a PURE line parser + a mutex-guarded published snapshot. Traps it encodes: a source reporting nothing is **normal** (restic sends 0 bytes for a whole incremental run) and the progress source may only update on unit completion — degrade bytes → files → current item + elapsed, never fake a percentage |
 | Post-start async verification | controller/internal/stacks/manager.go `logPostStartStatus` | goroutine + sleep, INFO log, never blocks/fails the operation |
 | Startup wiring order | controller/cmd/controller/main.go | init-only setters (`SetStackProvider` M2 contract: exactly once, before scheduler/HTTP), scheduler registration block |
 
@@ -200,6 +203,8 @@
 | `escrowAgent` + `Server.escrowAgentFn/escrowStageFn/escrowStaleFn` | controller/internal/web/escrow_handlers.go (+ server.go fields) | `*agentapi.Client` / `PushOffboxPasswordForEscrow` / `report.EscrowAutoConfirmer.StaleBlob` (SetEscrowStale) | `fakeEscrowAgent` + fn injections in escrow_wizard_test.go — call-ORDER assertions (stage BEFORE trigger) + agent-never-called gates. The claim leg is the ONLY surface R crosses: no-store, never logged, never templated |
 | `offboxCeremonyWaitState` + `escrowCeremonyGraceWindow` | controller/internal/web/handlers.go | pure pick: (awaiting, timedOut) from `OffboxTarget.{EscrowState,CeremonyCompletedAt}` — the v0.138.0 "megerősítésre vár" card. Stamp SET on claim (escrow_handlers.go), CLEARED on the flip (main.go Flip + offbox_handlers.go manual confirm) | escrow_wait_state_test.go truth table (escrowed/unstamped/unparseable → plain CTA; boundary via `>=`) |
 | `Manager.sambaUpFn` / `sambaPasswdFn` / `sambaRunFn` (func seams) | controller/internal/stacks/manager.go (fields) + samba.go | nil → `composeUp` / `docker exec smbpasswd` (STDIN) / `containerRunning("felhom-samba")` | injected in controller/internal/stacks/samba_test.go — the idempotency test asserts the up-seam is called **zero** times when config is unchanged; the passwd seam means no unit test ever handles a real secret or touches docker |
+| `Manager.sambaImgFn` (func seam) | controller/internal/stacks/manager.go (field) + samba.go | nil → `docker image inspect <infra.SambaImage>` | drives the 4b card's pulling-vs-starting decision, which MUST be taken before `compose up` (afterwards the image is always present) |
+| `Manager.offboxStreamRunner` + `SetOffboxStreamRunner` | controller/internal/backup/offbox_progress.go | nil → `defaultOffboxStreamRunner` (real `restic`, stdout scanned live) | streaming sibling of `offboxRunner`; fakes emit canned `--json` status lines in offbox_progress_test.go, so the whole progress path runs with no restic, network or repo |
 | `report.SetPendingControllerLog` / `SetControllerLogSource` | controller/internal/report/selftail.go | ACK-armed consume-once self-log pull (the logtail.go shape) | selftail_test.go; source = `logBuffer.Lines`, wired once in main.go |
 | `util.ParseVersion` / `util.Version.Compare` | controller/internal/util/version.go | THE one semver comparator (house rule: never a second) — selfupdate aliases it; agentapi's MinAgent comparison uses it | rejects pre-release/dev/latest (callers fall back, never trust); numeric compare (0.100 > 0.81) |
 | `agentapi.AgentVersionReporter` + `featureMinAgent` | controller/internal/agentapi/features.go | version-first Supports (v0.82.0 header channel); probe = fallback for header-less agents | a coupled feature adds BOTH a featureProbes row AND a featureMinAgent row; v0.116.0: `SupportsWithSource` also reports HOW the verdict was reached (version/probe-cache/probe) for the gate log line |