getValidationErrors method
Gets validation error messages.
Returns a list of human-readable error messages explaining why the interaction is invalid. Called when validate returns false.
Defaults to empty list.
Implementation
@override
List<String> getValidationErrors() {
final errors = <String>[];
if (id.isEmpty) errors.add('ID cannot be empty');
if (data.isEmpty) errors.add('Data cannot be empty');
return errors;
}