feat: add todo cache repository and precise invalidation

apps/lib/features/todo/data/todo_api.dart

@@ -17,6 +17,10 @@ class TodoApi {
     return data.map((json) => TodoResponse.fromJson(json)).toList();
   }
 
+  Future<List<TodoResponse>> getPendingTodos() {
+    return getTodos(status: 'pending');
+  }
+
   Future<TodoResponse> getTodo(String id) async {
     final response = await _client.get('$_prefix/$id');
     return TodoResponse.fromJson(response.data);

apps/lib/features/todo/data/todo_repository.dart

@@ -0,0 +1,79 @@
+import 'dart:async';
+
+import '../../../core/cache/cache_entry.dart';
+import '../../../core/cache/cache_invalidator.dart';
+import '../../../core/cache/hybrid_cache_store.dart';
+import 'todo_api.dart';
+
+class TodoRepository {
+  static const String pendingListKey = 'todo:list:pending';
+
+  final TodoApi api;
+  final HybridCacheStore store;
+  final CacheInvalidator invalidator;
+  final DateTime Function() now;
+
+  TodoRepository({
+    required this.api,
+    required this.store,
+    required this.invalidator,
+    DateTime Function()? now,
+  }) : now = now ?? DateTime.now;
+
+  Future<List<TodoResponse>> getPendingTodos({
+    bool forceRefresh = false,
+  }) async {
+    if (!forceRefresh) {
+      final cached = await store.read<CacheEntry<List<TodoResponse>>>(
+        pendingListKey,
+      );
+      if (cached != null) {
+        return cached.value;
+      }
+    }
+
+    final remote = await api.getPendingTodos();
+    await store.write<CacheEntry<List<TodoResponse>>>(
+      pendingListKey,
+      CacheEntry(value: remote, fetchedAt: now()),
+    );
+    return remote;
+  }
+
+  Future<void> completeTodo(String id) async {
+    final cached = await store.read<CacheEntry<List<TodoResponse>>>(
+      pendingListKey,
+    );
+    if (cached != null) {
+      final next = cached.value
+          .map(
+            (todo) => todo.id == id
+                ? todo.copyWith(status: 'completed', completedAt: now())
+                : todo,
+          )
+          .toList(growable: false);
+      await store.write<CacheEntry<List<TodoResponse>>>(
+        pendingListKey,
+        CacheEntry(value: next, fetchedAt: now()),
+      );
+    }
+
+    invalidator.invalidate(pendingListKey);
+    try {
+      await api.completeTodo(id);
+    } catch (error) {
+      if (cached != null) {
+        await store.write<CacheEntry<List<TodoResponse>>>(
+          pendingListKey,
+          cached,
+        );
+      }
+      rethrow;
+    }
+  }
+
+  Future<void> invalidatePending() {
+    invalidator.invalidate(pendingListKey);
+    return Future<void>.value();
+  }
+}

apps/lib/features/todo/ui/screens/todo_quadrants_screen.dart

@@ -16,6 +16,7 @@ import '../../../../shared/widgets/toast/toast_type.dart';
 import '../../../calendar/ui/calendar_state_manager.dart';
 import '../../../calendar/ui/widgets/bottom_dock.dart';
 import '../../data/todo_api.dart';
+import '../../data/todo_repository.dart';
 
 class TodoQuadrantsScreen extends StatefulWidget {
   const TodoQuadrantsScreen({super.key});
@@ -26,6 +27,7 @@ class TodoQuadrantsScreen extends StatefulWidget {
 
 class _TodoQuadrantsScreenState extends State<TodoQuadrantsScreen> {
   final TodoApi _todoApi = sl<TodoApi>();
+  final TodoRepository _todoRepository = sl<TodoRepository>();
 
   List<TodoResponse> _todos = [];
   bool _isLoading = true;
@@ -210,7 +212,9 @@ class _TodoQuadrantsScreenState extends State<TodoQuadrantsScreen> {
     });
 
     try {
-      final todos = await _todoApi.getTodos(status: 'pending');
+      final todos = await _todoRepository.getPendingTodos(
+        forceRefresh: !showPageLoader,
+      );
       if (!mounted) {
         return;
       }
@@ -263,7 +267,7 @@ class _TodoQuadrantsScreenState extends State<TodoQuadrantsScreen> {
 
   Future<void> _completeTodo(TodoResponse todo) async {
     try {
-      await _todoApi.completeTodo(todo.id);
+      await _todoRepository.completeTodo(todo.id);
       if (mounted) {
         Toast.show(context, '已完成', type: ToastType.success);
       }