loadSettings method
Loads the app origin from the shared preferences.
If the app origin is not present in the shared preferences, it sets the default value to 'wss://caesar-transfer-iu.shuttleapp.rs'.
Returns a Future that completes with no value.
Implementation
Future<void> loadSettings() async {
SharedPreferences prefs = await SharedPreferences.getInstance();
appOrigin = prefs.getString('app_origin') ??
'wss://caesar-transfer-iu.shuttleapp.rs'; // Load the app origin
}