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/services/todo.service.ts

@@ -0,0 +1,80 @@
+import { apiClient } from './api';
+import type {
+  Todo,
+  CreateTodoRequest,
+  UpdateTodoRequest,
+} from '@/types';
+
+class TodoServiceClass {
+  async create(data: CreateTodoRequest): Promise<Todo> {
+    try {
+      const response = await apiClient.post<{ success: boolean; data: Todo }>('/todos', data);
+      if (response.data.success && response.data.data) {
+        return response.data.data;
+      }
+      throw new Error('创建失败');
+    } catch (error: any) {
+      throw new Error(error.response?.data?.error || '创建待办失败');
+    }
+  }
+
+  async getUserTodos(params?: { status?: string; page?: number; limit?: number }): Promise<Todo[]> {
+    const queryParams = new URLSearchParams();
+    if (params?.status) queryParams.append('status', params.status);
+    if (params?.page) queryParams.append('page', params.page.toString());
+    if (params?.limit) queryParams.append('limit', params.limit.toString());
+
+    const url = `/todos${queryParams.toString() ? `?${queryParams.toString()}` : ''}`;
+    const response = await apiClient.get<{ success: boolean; data: Todo[] }>(url);
+    return response.data.data || [];
+  }
+
+  async getPendingTodos(): Promise<Todo[]> {
+    const response = await apiClient.get<{ success: boolean; data: Todo[] }>('/todos/pending');
+    return response.data.data || [];
+  }
+
+  async getCompletedTodos(): Promise<Todo[]> {
+    const response = await apiClient.get<{ success: boolean; data: Todo[] }>('/todos/completed');
+    return response.data.data || [];
+  }
+
+  async getConfirmedTodos(): Promise<Todo[]> {
+    const response = await apiClient.get<{ success: boolean; data: Todo[] }>('/todos/confirmed');
+    return response.data.data || [];
+  }
+
+  async getById(id: string): Promise<Todo> {
+    try {
+      const response = await apiClient.get<{ success: boolean; data: Todo }>(`/todos/${id}`);
+      if (response.data.success && response.data.data) {
+        return response.data.data;
+      }
+      throw new Error('获取失败');
+    } catch (error: any) {
+      throw new Error(error.response?.data?.error || '待办不存在');
+    }
+  }
+
+  async update(id: string, data: UpdateTodoRequest): Promise<Todo> {
+    try {
+      const response = await apiClient.put<{ success: boolean; data: Todo }>(`/todos/${id}`, data);
+      if (response.data.success && response.data.data) {
+        return response.data.data;
+      }
+      throw new Error('更新失败');
+    } catch (error: any) {
+      throw new Error(error.response?.data?.error || '更新待办失败');
+    }
+  }
+
+  async delete(id: string): Promise<void> {
+    try {
+      await apiClient.delete(`/todos/${id}`);
+    } catch (error: any) {
+      throw new Error(error.response?.data?.error || '删除失败');
+    }
+  }
+}
+
+export const TodoService = new TodoServiceClass();