- Store client key in SQLite database instead of environment variable
- Add database migration from CLIENT_KEY environment variable to preserve existing keys
- Add admin UI with tabbed interface (Configuration and QR Code tabs)
- Implement QR code generation containing server config (address, port, key) for Android app
- Add functionality to regenerate client key with warning dialog
- Add buttons to download QR code as PNG and copy QR image to clipboard
- Add manual input fields for server address and port configuration
- Update requirements.txt with pyotp and qrcode dependencies