This PR updates the system tray icons to reflect both connection status and availability of updates. Now, the tray will show distinct icons for the following states: connected, disconnected, update available while connected, and update available while disconnected. This change improves user experience by providing a clear visual status indicator.
- Add new icons for connected and disconnected states with update available.
- Implement logic to switch icons based on connection status and update availability.
- Remove old icon references for default and update states.
