* Add Home Screen widget with VPN toggle and refactor app activation logic
- Add NetBirdWidgetExtension target with small/medium widget sizes
- Support direct connect/disconnect from widget via interactive buttons (iOS 17+)
- Detect missing VPN config or login-required state and open app via deep link
- Poll for stable VPN state after toggle to prevent loader getting stuck
- Add widget shared state keys to GlobalConstants and sync status from MainViewModel
- Fix false "authentication required" alert on app resume after widget disconnect
- Deduplicate app activation logic into shared startActivation/stopActivation
- Extract polling helpers: updateDetailsIfChanged, updatePeersIfChanged, applyExtensionStatus
evgeniyChepelev