fix: reset FileBrowser database when sources change

FileBrowser Quantum caches user source preferences in its SQLite
database. After a restore, the config.yaml gets correct sources but
the database still references the old "srv" source from docker-setup.sh
initial install. Now SyncFileBrowserMounts() detects when sources
changed and runs docker compose down -v to reset the database before
recreating.

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

controller/internal/web/handlers.go

@@ -1600,6 +1600,14 @@ func (s *Server) SyncFileBrowserMounts() {
 	// Generate and write config.yaml (sources + sidebar entries per drive)
 	configPath := stackDir + "/config.yaml"
 	fbConfig := generateFileBrowserConfig(paths)
+
+	// Detect if sources changed — if so, the database must be reset so
+	// FileBrowser picks up the new source list (user prefs cache old sources).
+	sourcesChanged := true
+	if oldConfig, err := os.ReadFile(configPath); err == nil {
+		sourcesChanged = string(oldConfig) != fbConfig
+	}
+
 	if err := os.WriteFile(configPath, []byte(fbConfig), 0644); err != nil {
 		s.logger.Printf("[ERROR] Failed to write FileBrowser config: %v", err)
 		return
@@ -1617,6 +1625,20 @@ func (s *Server) SyncFileBrowserMounts() {
 		return
 	}
 
+	// If sources changed, reset database so FileBrowser re-reads config.yaml.
+	// The database caches user source preferences from the old config.
+	if sourcesChanged {
+		s.logger.Printf("[INFO] FileBrowser sources changed — resetting database")
+		resetCtx, resetCancel := context.WithTimeout(context.Background(), 30*time.Second)
+		defer resetCancel()
+		// Stop container first, then remove the data volume
+		stop := exec.CommandContext(resetCtx, "docker", "compose", "down", "-v")
+		stop.Dir = stackDir
+		if out, err := stop.CombinedOutput(); err != nil {
+			s.logger.Printf("[WARN] FileBrowser down -v: %s — %v", strings.TrimSpace(string(out)), err)
+		}
+	}
+
 	// Recreate container — H16: use 60s timeout to prevent hanging indefinitely.
 	ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second)
 	defer cancel()