checkAndStartTutorial method
Checks if the user has seen the tutorial before and starts it if not.
Implementation
void checkAndStartTutorial() async {
final prefs = await SharedPreferences.getInstance();
final hasSeenTutorial =
prefs.getBool('seenTutorial_${_currentUser.email}') ?? false;
if (!hasSeenTutorial) {
_showLanguageSelection();
}
}