feat(mobile): #24 Flutter三合一APP骨架搭建

- Flutter 3.x 项目初始化（pubspec.yaml + 目录结构）
- 核心依赖：dio/go_router/provider/shared_preferences/hive/geolocator
- 统一登录页 + Token管理（TokenService + AuthInterceptor）
- 底部Tab三合一导航（供水/巡检/营收）
- 供水管理Tab：监测数据列表（MonitorListPage）
- 巡检Tab：任务列表+状态筛选+进度展示（PatrolTaskListPage）
- 营收Tab：抄表页面+账单列表（MeterReadingPage/BillListPage）
- 消息推送服务（PushService）
- GPS定位服务（LocationService）
- 拍照/相册服务（CameraService）
- 离线缓存服务（CacheService）
- Android/iOS打包配置+权限声明
- GoRouter路由+Auth认证守卫
- Provider状态管理

mobile-app/lib/features/patrol/models/patrol_task_model.dart

@@ -0,0 +1,59 @@
+/// 巡检任务模型
+class PatrolTaskModel {
+  final String id;
+  final String taskName;
+  final String taskCode;
+  final String routeName;
+  final String assignee;
+  final String status; // pending, in_progress, completed, overdue
+  final DateTime planDate;
+  final int checkpointTotal;
+  final int checkpointCompleted;
+  final String? remark;
+
+  PatrolTaskModel({
+    required this.id,
+    required this.taskName,
+    required this.taskCode,
+    required this.routeName,
+    required this.assignee,
+    required this.status,
+    required this.planDate,
+    required this.checkpointTotal,
+    required this.checkpointCompleted,
+    this.remark,
+  });
+
+  double get progress =>
+      checkpointTotal > 0 ? checkpointCompleted / checkpointTotal : 0;
+
+  factory PatrolTaskModel.fromJson(Map<String, dynamic> json) {
+    return PatrolTaskModel(
+      id: json['id']?.toString() ?? '',
+      taskName: json['taskName'] ?? '',
+      taskCode: json['taskCode'] ?? '',
+      routeName: json['routeName'] ?? '',
+      assignee: json['assignee'] ?? '',
+      status: json['status'] ?? 'pending',
+      planDate: DateTime.tryParse(json['planDate'] ?? '') ?? DateTime.now(),
+      checkpointTotal: json['checkpointTotal'] ?? 0,
+      checkpointCompleted: json['checkpointCompleted'] ?? 0,
+      remark: json['remark'],
+    );
+  }
+
+  Map<String, dynamic> toJson() {
+    return {
+      'id': id,
+      'taskName': taskName,
+      'taskCode': taskCode,
+      'routeName': routeName,
+      'assignee': assignee,
+      'status': status,
+      'planDate': planDate.toIso8601String(),
+      'checkpointTotal': checkpointTotal,
+      'checkpointCompleted': checkpointCompleted,
+      'remark': remark,
+    };
+  }
+}