feat: storage watchdog — USB disconnect detection, auto-stop, safe eject, auto-reconnect (v0.17.0)

New storage watchdog monitors registered storage paths every 5s. On disconnect
(3 consecutive probe failures), auto-stops affected apps, lazy-unmounts stale
VFS entries, fires alerts/notifications/hub report. On reconnect (UUID detected),
auto-remounts via fstab, cleans stale restic locks, offers app restart.

Safe disconnect UI for USB drives: confirmation dialog, stop apps, sync, unmount.
Disconnected state visible across all pages (dashboard, settings, backups, monitoring)
with hatched red bars and badges. Backup guards skip disconnected drives.

22 files changed (1 new: monitor/watchdog.go), ~1500 lines added.

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

controller/internal/report/builder.go

@@ -69,6 +69,14 @@ func BuildReport(
 		{Mount: "/", Label: "SSD", TotalGB: sysInfo.DiskTotalGB, UsedGB: sysInfo.DiskUsedGB, Percent: sysInfo.DiskPercent},
 	}
 	for _, sp := range storagePaths {
+		if sp.Disconnected {
+			r.Storage = append(r.Storage, StorageReport{
+				Mount:        sp.Path,
+				Label:        sp.Label,
+				Disconnected: true,
+			})
+			continue
+		}
 		di := system.GetDiskUsage(sp.Path)
 		if di == nil {
 			continue

controller/internal/report/types.go

@@ -39,11 +39,12 @@ 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"`
+	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"`
 }
 
 // ContainerReport holds aggregate and per-container status.