- Add biometric authentication button with Face ID/Touch ID/Windows Hello support
- Check WebAuthn support and platform authenticator availability on mount
- Handle biometric login flow with proper error handling
- Show biometric button only when device supports it
- Add loading states and user-friendly error messages
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>