feat: infra backup retention + version picker

Hub: GFS retention (7d/4w/3m, ~14 versions) in new infra_backup_versions
table. Recovery endpoint supports ?version=ID. New /versions API endpoint.
Dashboard shows backup history.

Controller: local drive backups rotated into history/ (last 5 versions).
Setup wizard shows version picker for Hub restores when multiple versions
exist. Scan results enriched with app names, disk count, history badge.
Local restore supports historical versions.

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

controller/internal/setup/scanner.go

@@ -17,15 +17,20 @@ import (
 
 // DriveBackup represents a found infra backup on a drive.
 type DriveBackup struct {
-	Device         string `json:"device"`
-	Label          string `json:"label"`
-	MountPoint     string `json:"mount_point"`
-	CustomerID     string `json:"customer_id"`
-	Timestamp      string `json:"timestamp"`
-	CtrlVersion    string `json:"controller_version"`
-	IntegrityOK    bool   `json:"integrity_ok"`
-	Error          string `json:"error,omitempty"`
-	WasTempMounted bool   `json:"-"`
+	Device         string   `json:"device"`
+	Label          string   `json:"label"`
+	MountPoint     string   `json:"mount_point"`
+	CustomerID     string   `json:"customer_id"`
+	Timestamp      string   `json:"timestamp"`
+	CtrlVersion    string   `json:"controller_version"`
+	IntegrityOK    bool     `json:"integrity_ok"`
+	Error          string   `json:"error,omitempty"`
+	StackCount     int      `json:"stack_count"`
+	StackNames     []string `json:"stack_names,omitempty"`
+	DiskCount      int      `json:"disk_count"`
+	IsHistory      bool     `json:"is_history"`
+	HistoryFile    string   `json:"history_file,omitempty"`
+	WasTempMounted bool     `json:"-"`
 }
 
 // lsblkOutput represents the JSON output of lsblk.
@@ -114,10 +119,8 @@ func ScanDrivesForInfraBackups(logger *log.Logger, debug bool) ([]DriveBackup, e
 			continue
 		}
 
-		result := scanPartition(part, mountedFS, logger)
-		if result != nil {
-			results = append(results, *result)
-		}
+		partResults := scanPartition(part, mountedFS, logger)
+		results = append(results, partResults...)
 	}
 
 	logger.Printf("[INFO] Setup: drive scan complete — found %d backup(s)", countValid(results))
@@ -137,7 +140,7 @@ func CleanupTempMounts(results []DriveBackup, logger *log.Logger) {
 	}
 }
 
-func scanPartition(part lsblkDevice, mountedFS map[string]string, logger *log.Logger) *DriveBackup {
+func scanPartition(part lsblkDevice, mountedFS map[string]string, logger *log.Logger) []DriveBackup {
 	label := ""
 	if part.Label != nil {
 		label = *part.Label
@@ -187,10 +190,12 @@ func scanPartition(part lsblkDevice, mountedFS map[string]string, logger *log.Lo
 		return nil
 	}
 
-	// Found backup — read and validate
-	_, meta, err := backup.ReadLocalInfraBackup(mountPoint)
+	var results []DriveBackup
 
-	result := &DriveBackup{
+	// Read current backup
+	backupData, meta, err := backup.ReadLocalInfraBackup(mountPoint)
+
+	current := DriveBackup{
 		Device:         part.Path,
 		Label:          label,
 		MountPoint:     mountPoint,
@@ -198,24 +203,52 @@ func scanPartition(part lsblkDevice, mountedFS map[string]string, logger *log.Lo
 	}
 
 	if err != nil {
-		result.IntegrityOK = false
-		result.Error = err.Error()
+		current.IntegrityOK = false
+		current.Error = err.Error()
 		if meta != nil {
-			result.CustomerID = meta.CustomerID
-			result.Timestamp = meta.Timestamp
-			result.CtrlVersion = meta.ControllerVersion
+			current.CustomerID = meta.CustomerID
+			current.Timestamp = meta.Timestamp
+			current.CtrlVersion = meta.ControllerVersion
 		}
 	} else {
-		result.IntegrityOK = true
-		result.CustomerID = meta.CustomerID
-		result.Timestamp = meta.Timestamp
-		result.CtrlVersion = meta.ControllerVersion
+		current.IntegrityOK = true
+		current.CustomerID = meta.CustomerID
+		current.Timestamp = meta.Timestamp
+		current.CtrlVersion = meta.ControllerVersion
+		backup.ParseBackupCounts(backupData, &current.StackCount, &current.StackNames, &current.DiskCount)
 	}
 
-	logger.Printf("[INFO] Setup: found infra backup on %s (%s) — customer=%s, integrity=%v",
-		part.Path, label, result.CustomerID, result.IntegrityOK)
+	results = append(results, current)
 
-	return result
+	logger.Printf("[INFO] Setup: found infra backup on %s (%s) — customer=%s, integrity=%v",
+		part.Path, label, current.CustomerID, current.IntegrityOK)
+
+	// Also scan history directory for older versions
+	history := backup.ReadLocalInfraHistory(mountPoint)
+	for _, hv := range history {
+		hResult := DriveBackup{
+			Device:      part.Path,
+			Label:       label,
+			MountPoint:  mountPoint,
+			CustomerID:  hv.CustomerID,
+			Timestamp:   hv.Timestamp,
+			CtrlVersion: hv.ControllerVersion,
+			IntegrityOK: hv.IntegrityOK,
+			Error:       hv.Error,
+			StackCount:  hv.StackCount,
+			StackNames:  hv.StackNames,
+			DiskCount:   hv.DiskCount,
+			IsHistory:   true,
+			HistoryFile: hv.HistoryFile,
+		}
+		results = append(results, hResult)
+	}
+
+	if len(history) > 0 {
+		logger.Printf("[INFO] Setup: found %d historical backup version(s) on %s", len(history), part.Path)
+	}
+
+	return results
 }
 
 func readMountedFilesystems() map[string]string {