已完成用户APP首期功能开发

交付用户端首期页面、配套接口、后台资源及测试文档。用户APP构建、静态分析和三个管理后台构建通过；完整测试仍有2项失败，后端模型注释检查未通过，详见交付记录。

apps/user_app/lib/data/services/recharge_flow.dart

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+// 功能描述：充值创建前持久化及到账恢复，不将支付拉起视作到账；版本：1.0.0。
+import '../repositories/client_repository.dart';
+import '../../domain/models/recharge.dart';
+import 'recharge_draft_store.dart';
+import 'api_client.dart';
+
+/// 单个页面使用一个实例；所有网络写入前确认存储所属账号。
+class RechargeFlow {
+  RechargeFlow(this.repository, this.store);
+  final ClientRepository repository;
+  final RechargeDraftStore store;
+  bool _busy = false;
+
+  Future<Map<String, Object?>> create(PendingRecharge draft) async {
+    if (_busy) throw StateError('充值正在处理中');
+    _busy = true;
+    try {
+      final owner = await repository.rechargeDraftOwner();
+      final previous = await store.read(owner);
+      if (previous != null &&
+          (previous.request != draft.request ||
+              previous.amount != draft.amount ||
+              previous.channel != draft.channel ||
+              previous.payType != draft.payType)) {
+        throw StateError('请先查询待确认充值');
+      }
+      if (previous != null) {
+        // 重试先读取入账事实，避免到账后再次拉起原支付参数。
+        try {
+          final result = await repository.rechargeResult(previous.request);
+          if (result.amount != previous.amount || result.channel != previous.channel) {
+            throw StateError('充值结果与原请求不一致');
+          }
+          if (await repository.rechargeDraftOwner() != owner) throw StateError('充值账户已切换');
+          if (result.credited) return {'recharge_status': 23};
+        } on ApiException catch (error) {
+          // 明确不存在才允许使用相同请求重发，网络异常不能推断订单不存在。
+          if (error.code != 1112) rethrow;
+        }
+      }
+      await store.write(owner, draft);
+      if (await repository.rechargeDraftOwner() != owner) throw StateError('充值账户已切换');
+      return await repository.createRecharge(
+        request: draft.request,
+        amount: draft.amount,
+        channel: draft.channel,
+        payType: draft.payType,
+      );
+    } finally {
+      _busy = false;
+    }
+  }
+
+  /// 未到账、查询失败或业务关联异常均保留原请求，方便再次核对。
+  Future<RechargeRecord?> recover() async {
+    if (_busy) throw StateError('充值正在处理中');
+    _busy = true;
+    try {
+      final owner = await repository.rechargeDraftOwner();
+      final draft = await store.read(owner);
+      if (draft == null) return null;
+      if (await repository.rechargeDraftOwner() != owner) throw StateError('充值账户已切换');
+      final result = await repository.rechargeResult(draft.request);
+      if (result.amount != draft.amount || result.channel != draft.channel) {
+        throw StateError('充值结果与原请求不一致');
+      }
+      if (await repository.rechargeDraftOwner() != owner) throw StateError('充值账户已切换');
+      if (result.credited) await store.delete(owner);
+      return result;
+    } finally {
+      _busy = false;
+    }
+  }
+}