getFromSecure function
Gets a string value from secure storage or SharedPreferences as fallback
Implementation
Future<String?> getFromSecure(String key) async {
// For this implementation, we'll use SharedPreferences as a simple storage
// In a production app, you would use a more secure solution like flutter_secure_storage
final prefs = await SharedPreferences.getInstance();
return prefs.getString('onairos_$key');
}