Fix dependencies and add SDD v1.0

Changes:
- Fix Python dependency conflicts in requirements.txt
- Update to use compatible version ranges
- Add fix_dependencies.bat for easy dependency repair
- Create comprehensive DEPENDENCY_FIX.md guide
- Add complete System Design Document (SDD) v1.0

SDD v1.0 includes:
✅ System architecture with dual backend
✅ Complete database design (31 tables)
✅ API specifications
✅ Security design
✅ Deployment architecture
✅ Performance optimization strategies

Fixed Issues:
🐛 Flask/cryptography version conflicts
🐛 pip dependency resolver warnings

Documentation:
📚 DEPENDENCY_FIX.md - Dependency troubleshooting
📚 SDD_系統設計文件_v1.0.md - Complete system design

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

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

fix_dependencies.bat

@@ -0,0 +1,57 @@
+@echo off
+REM 修復 Python 依賴衝突
+
+echo ========================================
+echo 修復 Python 依賴衝突
+echo ========================================
+echo.
+
+REM 檢查虛擬環境
+if not exist "venv\" (
+    echo [INFO] 建立虛擬環境...
+    python -m venv venv
+    if errorlevel 1 (
+        echo [ERROR] 無法建立虛擬環境
+        pause
+        exit /b 1
+    )
+)
+
+REM 啟動虛擬環境
+echo [INFO] 啟動虛擬環境...
+call venv\Scripts\activate.bat
+
+REM 升級 pip
+echo [INFO] 升級 pip...
+python -m pip install --upgrade pip
+echo.
+
+REM 清理舊的安裝
+echo [INFO] 清理舊的套件...
+pip uninstall -y Flask flask-jwt-extended pyopenssl cryptography
+echo.
+
+REM 安裝相容的 cryptography 版本
+echo [INFO] 安裝相容的 cryptography...
+pip install "cryptography>=41.0.0,<47.0.0"
+echo.
+
+REM 安裝其他依賴
+echo [INFO] 安裝其他依賴...
+pip install -r requirements.txt --upgrade
+echo.
+
+REM 驗證安裝
+echo [INFO] 驗證安裝...
+echo.
+pip list | findstr "Flask cryptography PyMySQL requests"
+echo.
+
+echo ========================================
+echo [SUCCESS] 依賴修復完成！
+echo ========================================
+echo.
+echo 現在可以執行: python app.py
+echo.
+
+pause