.env

```env
# Google OAuth
GOOGLE_CLIENT_ID=your_google_client_id.apps.googleusercontent.com
GOOGLE_CLIENT_SECRET=your_google_client_secret
GOOGLE_REDIRECT_URI=http://localhost:3000/auth/google/callback

# Session
SESSION_SECRET=your_session_secret_here

# OpenRouter
OPENROUTER_API_KEY=your_openrouter_api_key

# Server
PORT=3000
NODE_ENV=development
```