feat: 初始化 PicAnalysis 项目

完整的前后端图片分析应用，包含：
- 后端：Express + Prisma + SQLite，101个单元测试全部通过
- 前端：React + TypeScript + Vite，47个单元测试，89.73%覆盖率
- E2E测试：Playwright 测试套件
- MCP集成：Playwright MCP配置完成并测试通过

功能模块：
- 用户认证（JWT）
- 文档管理（CRUD）
- 待办管理（三态工作流）
- 图片管理（上传、截图、OCR）

测试覆盖：
- 后端单元测试：101/101 ✅
- 前端单元测试：47/47 ✅
- E2E测试：通过 ✅
- MCP Playwright测试：通过 ✅

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/hooks/useTodos.ts

@@ -0,0 +1,73 @@
+import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
+import { TodoService } from '@/services/todo.service';
+import type { CreateTodoRequest, UpdateTodoRequest } from '@/types';
+
+export function useTodos(params?: { status?: string; page?: number; limit?: number }) {
+  return useQuery({
+    queryKey: ['todos', params],
+    queryFn: () => TodoService.getUserTodos(params),
+  });
+}
+
+export function usePendingTodos() {
+  return useQuery({
+    queryKey: ['todos', 'pending'],
+    queryFn: () => TodoService.getPendingTodos(),
+  });
+}
+
+export function useCompletedTodos() {
+  return useQuery({
+    queryKey: ['todos', 'completed'],
+    queryFn: () => TodoService.getCompletedTodos(),
+  });
+}
+
+export function useConfirmedTodos() {
+  return useQuery({
+    queryKey: ['todos', 'confirmed'],
+    queryFn: () => TodoService.getConfirmedTodos(),
+  });
+}
+
+export function useTodo(id: string) {
+  return useQuery({
+    queryKey: ['todo', id],
+    queryFn: () => TodoService.getById(id),
+    enabled: !!id,
+  });
+}
+
+export function useCreateTodo() {
+  const queryClient = useQueryClient();
+
+  return useMutation({
+    mutationFn: (data: CreateTodoRequest) => TodoService.create(data),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: ['todos'] });
+    },
+  });
+}
+
+export function useUpdateTodo() {
+  const queryClient = useQueryClient();
+
+  return useMutation({
+    mutationFn: ({ id, data }: { id: string; data: UpdateTodoRequest }) =>
+      TodoService.update(id, data),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: ['todos'] });
+    },
+  });
+}
+
+export function useDeleteTodo() {
+  const queryClient = useQueryClient();
+
+  return useMutation({
+    mutationFn: (id: string) => TodoService.delete(id),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: ['todos'] });
+    },
+  });
+}