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

一键启动.bat

@@ -0,0 +1,55 @@
+@echo off
+chcp 65001 >nul
+echo ========================================
+echo   AI临床研究平台 - 一键启动脚本
+echo ========================================
+echo.
+
+echo [1/5] 检查Docker容器状态...
+docker ps >nul 2>&1
+if errorlevel 1 (
+    echo ❌ Docker未运行，请先启动Docker Desktop
+    pause
+    exit /b 1
+)
+
+echo [2/5] 启动PostgreSQL和Redis容器...
+cd /d "%~dp0"
+docker-compose up -d
+if errorlevel 1 (
+    echo ❌ Docker容器启动失败
+    pause
+    exit /b 1
+)
+echo ✅ 数据库容器启动成功
+
+echo [3/5] 等待数据库就绪...
+timeout /t 5 /nobreak >nul
+
+echo [4/5] 启动后端服务（新窗口）...
+start "AI临床研究平台-后端" cmd /k "cd /d %~dp0backend && npm run dev"
+echo ✅ 后端服务启动中...
+
+echo [5/5] 等待后端启动...
+timeout /t 3 /nobreak >nul
+
+echo [6/6] 启动前端服务（新窗口）...
+start "AI临床研究平台-前端" cmd /k "cd /d %~dp0frontend && npm run dev"
+echo ✅ 前端服务启动中...
+
+echo.
+echo ========================================
+echo   启动完成！
+echo ========================================
+echo.
+echo 后端地址: http://localhost:3001
+echo 前端地址: http://localhost:3000
+echo.
+echo 请等待10秒后访问前端地址
+echo.
+timeout /t 10 /nobreak
+start http://localhost:3000
+echo.
+echo 按任意键关闭此窗口...
+pause >nul
+