🔧 Fix alembic config and add Docker database support

Fix:
- Fix alembic.ini version_path_separator syntax error
- Add scripts to start with Docker database
- Add automatic fix and start script

New files:
- start_with_docker_db.bat: Start with Docker PostgreSQL
- fix_and_start.bat: Auto-fix and start with options

🚀 Generated with [Claude Code](https://claude.com/claude-code)

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

fix_and_start.bat

@@ -0,0 +1,140 @@
+@echo off
+title QQuiz - Fix and Start
+color 0E
+
+echo.
+echo ========================================
+echo   QQuiz - Automatic Fix and Start
+echo ========================================
+echo.
+
+cd /d "%~dp0"
+
+REM Check if .env exists
+if not exist ".env" (
+    echo Creating .env file...
+    copy .env.example .env >nul
+    echo.
+    echo IMPORTANT: Edit .env and set your OPENAI_API_KEY
+    echo Opening .env file...
+    timeout /t 2 /nobreak >nul
+    notepad .env
+    echo.
+    echo Save and close .env, then press any key to continue...
+    pause >nul
+)
+
+echo.
+echo Choose database option:
+echo.
+echo [1] Use Docker (Recommended - Easy)
+echo [2] Use Local PostgreSQL (Advanced)
+echo.
+choice /C 12 /M "Select option"
+
+if %errorlevel% equ 1 (
+    echo.
+    echo Using Docker PostgreSQL...
+    echo.
+
+    REM Check Docker
+    docker --version >nul 2>&1
+    if %errorlevel% neq 0 (
+        echo ERROR: Docker not found!
+        echo.
+        echo Please install Docker Desktop:
+        echo https://www.docker.com/products/docker-desktop/
+        echo.
+        echo After installing Docker, run this script again.
+        pause
+        exit /b 1
+    )
+
+    echo Starting PostgreSQL in Docker...
+    docker-compose up -d postgres
+
+    if %errorlevel% neq 0 (
+        echo.
+        echo Docker failed to start. Trying to fix...
+        docker-compose down
+        docker-compose up -d postgres
+    )
+
+    echo Waiting for database...
+    timeout /t 8 /nobreak >nul
+
+) else (
+    echo.
+    echo Using Local PostgreSQL...
+    echo.
+    echo Make sure PostgreSQL is running on port 5432
+    echo.
+    echo If you see connection errors, you need to:
+    echo 1. Start PostgreSQL service
+    echo 2. Or install PostgreSQL from https://www.postgresql.org/download/
+    echo 3. Or choose option 1 to use Docker instead
+    echo.
+    pause
+)
+
+echo.
+echo ========================================
+echo   Starting Backend...
+echo ========================================
+echo.
+
+cd backend
+
+if not exist "venv\Scripts\activate.bat" (
+    echo Creating virtual environment...
+    python -m venv venv
+)
+
+echo Installing dependencies...
+call venv\Scripts\activate.bat
+pip install -q -r requirements.txt -i https://pypi.tuna.tsinghua.edu.cn/simple
+
+echo.
+echo Running database migrations...
+alembic upgrade head
+
+if %errorlevel% neq 0 (
+    echo.
+    echo WARNING: Database migration failed
+    echo The app will try to create tables automatically
+    echo.
+)
+
+cd ..
+
+echo.
+echo Starting services...
+echo.
+
+start "QQuiz Backend" cmd /k "cd /d %~dp0backend && call venv\Scripts\activate.bat && echo Backend: http://localhost:8000 && echo Docs: http://localhost:8000/docs && echo. && uvicorn main:app --reload"
+
+timeout /t 8 /nobreak >nul
+
+start "QQuiz Frontend" cmd /k "cd /d %~dp0frontend && echo Frontend: http://localhost:3000 && echo. && npm start"
+
+echo.
+echo ========================================
+echo   SUCCESS! QQuiz is starting...
+echo ========================================
+echo.
+echo Frontend: http://localhost:3000
+echo Backend:  http://localhost:8000
+echo.
+echo Login: admin / admin123
+echo.
+echo ========================================
+echo.
+
+timeout /t 5 /nobreak >nul
+start http://localhost:3000
+
+echo.
+echo System is running...
+echo Close backend/frontend windows to stop
+echo.
+pause