open method
void
open()
Open the survey.
Implementation
void open() {
_currentAppearanceId =
'${DateTime.now().millisecondsSinceEpoch}_${_random.nextInt(100000)}';
state.value = FeedbackSurveyState.open;
inputValue.value = '';
_updateLastShownTime();
// Log appearance event
_logEvent('appeared');
}