signup method
Implementation
Future<AppUser> signup(String name, String email, String password) async {
await Future.delayed(const Duration(seconds: 1));
final user = AppUser(
id: _uuid.v4(),
name: name,
email: email,
);
_currentUser = user;
await _storage.saveSetting('userId', user.id);
await _storage.saveSetting('profileName', name);
return user;
}