feat(v0.11.6): FileBrowser auto-mount sync + UI polish

- Add syncFileBrowserMounts() and generateFileBrowserCompose() to handlers.go
- Call syncFileBrowserMounts() after storage path add (storage init) and remove
- settings.html: red 'Nincs csatolva!' badge → yellow 'Rendszermeghajtón' (badge-warn)
- settings.html: 'Alapértelmezett' button → 'Legyen alapértelmezett' (action clarity)
- storage_init.html: replace disk-usage zone gradient bar with clean progress-bar-task
- style.css: add .badge-warn and .progress-bar-task CSS classes

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

controller/internal/web/storage_handlers.go

@@ -250,6 +250,8 @@ func (s *Server) storageInitAPIHandler(w http.ResponseWriter, r *http.Request) {
 			s.logger.Printf("[WARN] Failed to register storage path after init: %v", err)
 		} else {
 			s.logger.Printf("[INFO] Storage path registered: %s (%s)", mountPath, label)
+			// Sync FileBrowser mounts with new storage path
+			s.syncFileBrowserMounts()
 		}
 	}()