v0.57.0: stable host-storage list + per-app Tier-2 config panel

Part A of the UI-fixes/storage-spike spec.

A1: enrichHostStorageTargets sorts /api/host-metrics storage_targets
server-side and attaches friendly Hungarian labels + purpose, fixing the
#host-storage-bars reorder-on-poll bug. Display labels only — PVE storage
ids are never renamed.

A2: new GET/POST /stacks/{name}/backup Tier-2 config panel; the "2. mentés"
Beállítás button is repointed there from the dead-end deploy page. Customer
can pin a target drive or disable Tier 2; preference is preserved across the
runner's status writes. Always visible (single-SSD + non-HDD apps included).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

controller/internal/web/agent_host_metrics_handler_test.go

@@ -0,0 +1,81 @@
+package web
+
+import (
+	"testing"
+
+	"gitea.dooplex.hu/admin/felhom-controller/internal/agentapi"
+)
+
+// enrichHostStorageTargets must produce a STABLE order regardless of how the agent enumerated the
+// storages (the #host-storage-bars reorder bug, item 2), and attach a friendly label + purpose per
+// entry without ever mutating the raw PVE id (Name).
+func TestEnrichHostStorageTargets_OrderAndLabels(t *testing.T) {
+	// Deliberately shuffled relative to the desired display order.
+	targets := []agentapi.StorageTarget{
+		{Name: "felhom-pbs", Type: "pbs"},
+		{Name: "local", Type: "local"},
+		{Name: "felhom-usb", Type: "usb"},
+		{Name: "local-lvm", Type: "lvmthin"},
+	}
+	enrichHostStorageTargets(targets)
+
+	wantOrder := []string{"felhom-usb", "local-lvm", "local", "felhom-pbs"}
+	for i, want := range wantOrder {
+		if targets[i].Name != want {
+			t.Fatalf("position %d = %q, want %q (full order: %v)", i, targets[i].Name, want, names(targets))
+		}
+	}
+
+	// Friendly labels attached; raw ids untouched.
+	for _, tgt := range targets {
+		if tgt.Label == "" || tgt.Purpose == "" {
+			t.Errorf("%s (%s): missing label/purpose (label=%q purpose=%q)", tgt.Name, tgt.Type, tgt.Label, tgt.Purpose)
+		}
+	}
+	if targets[0].Label != "Külső adattároló (USB)" {
+		t.Errorf("usb label = %q", targets[0].Label)
+	}
+	if targets[1].Label != "Belső SSD – rendszer és alkalmazások" {
+		t.Errorf("lvmthin label = %q", targets[1].Label)
+	}
+}
+
+// A second run with the same input must yield the same order (determinism / idempotence).
+func TestEnrichHostStorageTargets_Stable(t *testing.T) {
+	mk := func() []agentapi.StorageTarget {
+		return []agentapi.StorageTarget{
+			{Name: "b-usb", Type: "usb"},
+			{Name: "a-usb", Type: "usb"},
+			{Name: "local-lvm", Type: "lvmthin"},
+		}
+	}
+	a, b := mk(), mk()
+	enrichHostStorageTargets(a)
+	enrichHostStorageTargets(b)
+	for i := range a {
+		if a[i].Name != b[i].Name {
+			t.Fatalf("non-deterministic at %d: %q vs %q", i, a[i].Name, b[i].Name)
+		}
+	}
+	// Within the same tier, alphabetical by id.
+	if a[0].Name != "a-usb" || a[1].Name != "b-usb" {
+		t.Errorf("within-tier order = %v, want a-usb,b-usb first", names(a))
+	}
+}
+
+// An unrecognised type falls back to the raw id and an empty purpose.
+func TestEnrichHostStorageTargets_UnknownType(t *testing.T) {
+	targets := []agentapi.StorageTarget{{Name: "weird-store", Type: "zfspool"}}
+	enrichHostStorageTargets(targets)
+	if targets[0].Label != "weird-store" || targets[0].Purpose != "" {
+		t.Errorf("unknown type: label=%q purpose=%q, want raw id + empty", targets[0].Label, targets[0].Purpose)
+	}
+}
+
+func names(ts []agentapi.StorageTarget) []string {
+	out := make([]string, len(ts))
+	for i, t := range ts {
+		out[i] = t.Name
+	}
+	return out
+}