feat: drive migration & Tier 2 restic deprecation (v0.18.0)

Phase 1: Deprecate restic as Tier 2 method (rsync only), auto-migrate on startup
Phase 2: Enhanced per-app migration with backup awareness, DB dump copy, auto-cleanup
Phase 3: Full drive migration with decommissioned state, rollback support, wizard UI
Phase 4: Hub report includes decommissioned drive state

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

controller/internal/report/builder.go

@@ -69,6 +69,15 @@ func BuildReport(
 		{Mount: "/", Label: "SSD", TotalGB: sysInfo.DiskTotalGB, UsedGB: sysInfo.DiskUsedGB, Percent: sysInfo.DiskPercent},
 	}
 	for _, sp := range storagePaths {
+		if sp.Decommissioned {
+			r.Storage = append(r.Storage, StorageReport{
+				Mount:          sp.Path,
+				Label:          sp.Label,
+				Decommissioned: true,
+				MigratedTo:     sp.MigratedTo,
+			})
+			continue
+		}
 		if sp.Disconnected {
 			r.Storage = append(r.Storage, StorageReport{
 				Mount:        sp.Path,

controller/internal/report/infra_backup.go

@@ -75,12 +75,6 @@ func BuildInfraBackup(
 		logger.Printf("[WARN] Infra backup: could not read restic password file: %v", err)
 	}
 
-	// Cross-drive password is stored as plain text (not base64) because it's
-	// already a string in settings, unlike ResticPassword which comes from a file.
-	if pw := sett.GetCrossDriveResticPassword(); pw != "" {
-		ib.CrossDrivePassword = pw
-	}
-
 	// Collect disk layout from fstab + blkid
 	ib.DiskLayout = collectDiskLayout(systemDataPath)
 

controller/internal/report/types.go

@@ -39,12 +39,14 @@ type SystemReport struct {
 
 // StorageReport holds disk usage for a mount point.
 type StorageReport struct {
-	Mount        string  `json:"mount"`
-	Label        string  `json:"label,omitempty"`
-	TotalGB      float64 `json:"total_gb"`
-	UsedGB       float64 `json:"used_gb"`
-	Percent      float64 `json:"percent"`
-	Disconnected bool    `json:"disconnected,omitempty"`
+	Mount          string  `json:"mount"`
+	Label          string  `json:"label,omitempty"`
+	TotalGB        float64 `json:"total_gb"`
+	UsedGB         float64 `json:"used_gb"`
+	Percent        float64 `json:"percent"`
+	Disconnected   bool    `json:"disconnected,omitempty"`
+	Decommissioned bool    `json:"decommissioned,omitempty"`
+	MigratedTo     string  `json:"migrated_to,omitempty"`
 }
 
 // ContainerReport holds aggregate and per-container status.