add admin page, fix no legs infinite load on dashboard

lib/ui/app_shell.dart

@@ -1,3 +1,5 @@
+import 'dart:async';
+
 import 'package:dynamic_color/dynamic_color.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/material.dart';
@@ -221,6 +223,10 @@ class _MyAppState extends State<MyApp> {
               path: '/more/settings',
               builder: (context, state) => const SettingsPage(),
             ),
+            GoRoute(
+              path: '/more/admin',
+              builder: (context, state) => const AdminPage(),
+            ),
             GoRoute(
               path: '/legs/edit/:id',
               builder: (_, state) {
@@ -307,6 +313,7 @@ class _MyHomePageState extends State<MyHomePage> {
 
   bool _fetched = false;
   bool _railCollapsed = false;
+  Timer? _notificationsTimer;
 
   @override
   void didChangeDependencies() {
@@ -343,10 +350,28 @@ class _MyHomePageState extends State<MyHomePage> {
         if (data.notifications.isEmpty) {
           data.fetchNotifications();
         }
+        _startNotificationPolling();
       });
     });
   }
 
+  void _startNotificationPolling() {
+    _notificationsTimer?.cancel();
+    final auth = context.read<AuthService>();
+    if (!auth.isLoggedIn) return;
+    _notificationsTimer = Timer.periodic(const Duration(minutes: 2), (_) async {
+      if (!mounted) return;
+      final auth = context.read<AuthService>();
+      if (!auth.isLoggedIn) return;
+      final data = context.read<DataService>();
+      try {
+        await data.fetchNotifications();
+      } catch (_) {
+        // Errors already logged inside data service.
+      }
+    });
+  }
+
   @override
   Widget build(BuildContext context) {
     final uri = GoRouterState.of(context).uri;
@@ -895,4 +920,10 @@ class _MyHomePageState extends State<MyHomePage> {
     _forwardHistory.clear();
     context.go(tabDestinations[index]);
   }
+
+  @override
+  void dispose() {
+    _notificationsTimer?.cancel();
+    super.dispose();
+  }
 }