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/handlers.go

@@ -614,6 +614,8 @@ type AppBackupRow struct {
 	Tier2DestDisconnected bool
 	// Tier2 destination drive is inactive (Schedulable=false, backup paused)
 	Tier2DestInactive bool
+	// Tier2UserDisabled — customer turned Tier 2 off for this app from the config panel.
+	Tier2UserDisabled bool
 
 	// Warnings accumulated for this app
 	Warnings []string
@@ -701,7 +703,10 @@ func (s *Server) buildAppBackupRows(status *backup.FullBackupStatus) []AppBackup
 
 		// Tier 2 (off-drive copy) status, from the config the Tier 2 runner persists.
 		if cd := s.settings.GetCrossDriveConfig(app.StackName); cd != nil {
-			if cd.LastStatus == "no_target" {
+			row.Tier2UserDisabled = cd.UserDisabled
+			if cd.UserDisabled {
+				// Customer turned Tier 2 off — show nothing more; the panel button still appears.
+			} else if cd.LastStatus == "no_target" {
 				// Auto Tier 2 found no off-drive target — surface the honest reason (no silent gap).
 				row.Tier2Configured = false
 				row.Tier2StatusBadge = "Nincs 2. meghajtó"