completeOnboarding method

Implementation

Future<void> completeOnboarding() async {
  final userId = _client.auth.currentUser?.id;
  if (userId == null) return;
  await _client
      .from('profiles')
      .update({
        'onboarding_step': 'completed',
        'onboarding_completed_at': DateTime.now().toIso8601String(),
      })
      .eq('id', userId);
}