▶️ Google ile Giriş
- UI: /giris > 'Google ile GiriÅŸ' button
- GET /api/auth/google → 302 Redirect to accounts.google.com
- Google consent screen → onay
- Callback /api/auth/google/callback?code=...
- Backend: code → Google token exchange → user info
- Mevcut user mu yeni mi check → otomatik register/login
- Set session cookie + redirect /
🔌 Endpoint'ler
GET/api/auth/google