fix: create mock user to resolve FK constraint issue

Issues fixed:
1. Frontend port is 3000 (not 5173)
2. Projects API returns 500 due to missing user
3. Foreign key constraint violation on projects_user_id_fkey

Solutions:
- Created create-mock-user.ts script
- Added user-mock-001 to database
- Created startup guide (娴嬭瘯鍜屽惎鍔?md)
- Created one-click launcher (涓€閿惎鍔?bat)
- Created diagnostic tool (璇婃柇闂.bat)

New files:
- backend/src/scripts/create-mock-user.ts
- 娴嬭瘯鍜屽惎鍔?md
- 涓€閿惎鍔?bat
- 璇婃柇闂.bat

诊断问题.bat

@@ -0,0 +1,115 @@
+@echo off
+chcp 65001 >nul
+echo ========================================
+echo   系统诊断工具
+echo ========================================
+echo.
+
+echo [检查1] Docker运行状态...
+docker ps >nul 2>&1
+if errorlevel 1 (
+    echo ❌ Docker未运行
+    echo    解决方案: 启动Docker Desktop
+) else (
+    echo ✅ Docker正在运行
+    echo.
+    echo    运行中的容器:
+    docker ps --format "table {{.Names}}\t{{.Status}}\t{{.Ports}}"
+)
+echo.
+
+echo [检查2] PostgreSQL容器...
+docker ps | findstr postgres >nul
+if errorlevel 1 (
+    echo ❌ PostgreSQL容器未运行
+    echo    解决方案: docker-compose up -d
+) else (
+    echo ✅ PostgreSQL容器正在运行
+)
+echo.
+
+echo [检查3] Redis容器...
+docker ps | findstr redis >nul
+if errorlevel 1 (
+    echo ❌ Redis容器未运行
+    echo    解决方案: docker-compose up -d
+) else (
+    echo ✅ Redis容器正在运行
+)
+echo.
+
+echo [检查4] 后端服务...
+curl -s http://localhost:3001/health >nul 2>&1
+if errorlevel 1 (
+    echo ❌ 后端服务未响应
+    echo    解决方案: 
+    echo    1. cd backend
+    echo    2. npm run dev
+) else (
+    echo ✅ 后端服务正常
+    echo.
+    echo    健康检查响应:
+    curl -s http://localhost:3001/health
+)
+echo.
+
+echo [检查5] 前端服务...
+curl -s http://localhost:3000 >nul 2>&1
+if errorlevel 1 (
+    echo ❌ 前端服务未响应
+    echo    解决方案:
+    echo    1. cd frontend
+    echo    2. npm run dev
+) else (
+    echo ✅ 前端服务正常
+)
+echo.
+
+echo [检查6] 后端环境配置...
+if exist "backend\.env" (
+    echo ✅ backend\.env 文件存在
+    echo.
+    echo    检查API Keys配置:
+    findstr /C:"DEEPSEEK_API_KEY" backend\.env | findstr /V "your_" >nul
+    if errorlevel 1 (
+        echo    ⚠️  DEEPSEEK_API_KEY 可能未配置
+    ) else (
+        echo    ✅ DEEPSEEK_API_KEY 已配置
+    )
+    findstr /C:"DASHSCOPE_API_KEY" backend\.env | findstr /V "your_" >nul
+    if errorlevel 1 (
+        echo    ⚠️  DASHSCOPE_API_KEY 可能未配置
+    ) else (
+        echo    ✅ DASHSCOPE_API_KEY 已配置
+    )
+) else (
+    echo ❌ backend\.env 文件不存在
+    echo    解决方案:
+    echo    1. cd backend
+    echo    2. copy .env.example .env
+    echo    3. 编辑 .env 文件，填入API Keys
+)
+echo.
+
+echo [检查7] 数据库迁移状态...
+if exist "backend\prisma\migrations" (
+    echo ✅ 数据库迁移文件存在
+) else (
+    echo ❌ 数据库迁移文件不存在
+    echo    解决方案:
+    echo    1. cd backend
+    echo    2. npx prisma migrate dev
+)
+echo.
+
+echo ========================================
+echo   诊断完成
+echo ========================================
+echo.
+echo 如果所有检查都通过但仍有问题，请:
+echo 1. 查看后端终端的完整日志
+echo 2. 查看浏览器控制台的Network标签
+echo 3. 运行: cd backend ^&^& npx prisma studio 检查数据库
+echo.
+pause
+