v0.11.8 — Per-App Cross-Drive Backup (3-2-1 rule)

New feature: backup app data to a secondary storage drive to satisfy
the "different media" requirement of the 3-2-1 backup rule.

- settings.go: CrossDriveBackup struct, AppBackupPrefs.CrossDrive field,
  getter/setter methods, GetOrCreateCrossDrivePassword, preserves
  cross-drive config when toggling nightly backup

- crossdrive.go (new): CrossDriveRunner with rsync and restic backends.
  Validates destination (mount point, writable), prevents source/dest
  overlap, per-app concurrency lock, persists last_run/status/size.

- main.go: wire CrossDriveRunner, register cross-drive-daily (03:30)
  and cross-drive-weekly (04:30 Sundays) scheduler jobs

- router.go: 4 new API endpoints — save config, trigger run, get status,
  run-all. Router now accepts Settings and CrossDriveRunner.

- server.go: Server struct accepts CrossDriveRunner, new web route
  POST /settings/cross-backup/{name}

- handlers.go: deployHandler populates CrossDriveConfig, BackupDestPaths,
  BackupDestWarning, AppBackupEnabled. settingsCrossBackupHandler saves
  config. backupsHandler builds CrossDriveSummary, UnconfiguredApps,
  CrossDriveWarnings for backup page.

- deploy.html: "Biztonsági mentés" card with destination/method/schedule
  dropdowns, last-run status, manual trigger button, flash messages.

- backups.html: "Másolatok másik meghajtóra" section with per-app
  status rows, unconfigured app warnings, "Összes futtatása most" button.

- style.css: margin-bottom fix for .deploy-stale-data, new cross-drive
  card and list styles.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

controller/cmd/controller/main.go

@@ -116,12 +116,13 @@ func main() {
 
 	// --- Initialize backup manager ---
 	var backupMgr *backup.Manager
+	stackProv := &stackAdapter{
+		mgr:             stackMgr,
+		getStoragePaths: func() []settings.StoragePath { return sett.GetStoragePaths() },
+	}
 	if cfg.Backup.Enabled {
 		backupMgr = backup.NewManager(cfg, pinger, sett, logger)
-		backupMgr.SetStackProvider(&stackAdapter{
-			mgr:             stackMgr,
-			getStoragePaths: func() []settings.StoragePath { return sett.GetStoragePaths() },
-		})
+		backupMgr.SetStackProvider(stackProv)
 		backupMgr.AfterBackup = func() {
 			nextDBDump := scheduler.NextDailyRun(cfg.Backup.DBDumpSchedule)
 			nextBackup := scheduler.NextDailyRun(cfg.Backup.ResticSchedule)
@@ -130,6 +131,9 @@ func main() {
 		go backupMgr.LoadSnapshotHistory()
 	}
 
+	// --- Initialize cross-drive backup runner ---
+	crossDriveRunner := backup.NewCrossDriveRunner(sett, stackProv, logger)
+
 	// --- Initialize alert manager ---
 	alertMgr := web.NewAlertManager(logger)
 
@@ -212,6 +216,18 @@ func main() {
 		})
 	}
 
+	// Cross-drive backup — daily at 03:30 (after main backup at 03:00)
+	sched.Daily("cross-drive-daily", "03:30", func(ctx context.Context) error {
+		return crossDriveRunner.RunAllScheduled(ctx, "daily")
+	})
+	// Cross-drive weekly — Sunday 04:30 (after integrity check at 04:00)
+	sched.Daily("cross-drive-weekly", "04:30", func(ctx context.Context) error {
+		if time.Now().Weekday() != time.Sunday {
+			return nil
+		}
+		return crossDriveRunner.RunAllScheduled(ctx, "weekly")
+	})
+
 	// Metrics prune — daily at 04:00
 	if metricsStore != nil {
 		sched.Daily("metrics-prune", "04:00", func(ctx context.Context) error {
@@ -300,10 +316,10 @@ func main() {
 	}()
 
 	// --- Initialize API router ---
-	apiRouter := api.NewRouter(cfg, stackMgr, syncer, cpuCollector, backupMgr, metricsStore, logger)
+	apiRouter := api.NewRouter(cfg, sett, stackMgr, syncer, cpuCollector, backupMgr, crossDriveRunner, metricsStore, logger)
 
 	// --- Initialize web server ---
-	webServer := web.NewServer(cfg, stackMgr, cpuCollector, backupMgr, sched, sett, alertMgr, notifier, logger, Version)
+	webServer := web.NewServer(cfg, stackMgr, cpuCollector, backupMgr, crossDriveRunner, sched, sett, alertMgr, notifier, logger, Version)
 
 	// --- Build HTTP mux ---
 	mux := http.NewServeMux()