- Add real-time chat between customers and staff via WebSocket
- Add HTTP polling fallback when WebSocket unavailable
- Chat auto-closes when worker ends conversation with dialog notification
- Add user search API for group order invites (phone/email/name)
- Store group order invites in app state
- Add login check before starting chat with sign-in prompt
- Remove table change button (not allowed currently)
- Fix About screen to show dynamic version from pubspec
- Update snackbar styling to green with black text
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
