Phase 1 #24: Flutter 移动端框架（三合一 APP 骨架）

- pubspec.yaml: dio/provider/shared_preferences/flutter_map/geolocator
- main.dart: Provider 状态管理 + 登录守卫
- AuthService: Token 管理 + Dio HTTP + SharedPreferences 持久化
- LoginPage: Material Design 登录页
- HomePage: 三合一 BottomTab 导航（供水/巡检/营收）
- 预留依赖: flutter_local_notifications/image_picker/permission_handler

mobile/pubspec.yaml

@@ -0,0 +1,22 @@
+name: water_management
+description: 智慧水务管理系统 - 移动端
+version: 1.0.0
+
+environment:
+  sdk: '>=3.2.0 <4.0.0'
+
+dependencies:
+  flutter: { sdk: flutter }
+  dio: ^5.4.0
+  provider: ^6.1.0
+  shared_preferences: ^2.2.0
+  flutter_map: ^6.1.0
+  latlong2: ^0.9.0
+  geolocator: ^11.0.0
+  image_picker: ^1.0.0
+  permission_handler: ^11.0.0
+  flutter_local_notifications: ^17.0.0
+
+dev_dependencies:
+  flutter_test: { sdk: flutter }
+  flutter_lints: ^3.0.0