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```bash

undefined

// Repository = the SINGLE WRITE PATH: persist first, then observers re-emit.
class OrderRepository {
  OrderRepository(this._db, this._clock);
  final AppDatabase _db;
  final Clock _clock;

  /// The only route an order reaches storage. Returns a typed Result, never throws.
  Future<Result<void, PersistFailure>> place(OrderDraft draft) async {
    try {
      await _db.transaction(() async {
        await _db.orderDao.insert(draft.toRow(_clock.now())); // durable FIRST
      });
      return const Ok(null); // watchers over the DAO re-emit on commit
    } on DriftException catch (e, s) {
      return Err(PersistFailure.write(cause: e, stack: s));
    }
  }
}

// ViewModel = one StreamNotifier per screen; state tracks EVERY DAO emission.
// Riverpod 3.x: extend the unified base class, opt into autoDispose on the provider.
class OrderListNotifier extends StreamNotifier<List<Order>> {
  @override
  Stream<List<Order>> build() =>
      ref.watch(orderRepositoryProvider).recent(); // re-emits on every commit

  Future<void> place(OrderDraft draft) async {
    final result = await ref.read(orderRepositoryProvider).place(draft);
    switch (result) {
      case Ok():        break;            // the watched stream re-emits the new state
      case Err(:final failure): state = AsyncError(failure, StackTrace.current);
    }
  }
}

final orderListProvider =
    StreamNotifierProvider.autoDispose<OrderListNotifier, List<Order>>(
  OrderListNotifier.new,
);

// View = dumb ConsumerWidget: reads one notifier, renders, no logic.
class OrderListScreen extends ConsumerWidget {
  const OrderListScreen({super.key});
  @override
  Widget build(BuildContext context, WidgetRef ref) {
    return ref.watch(orderListProvider).when(
      loading: () => const _OrdersSkeleton(),
      error: (e, _) => _RetryView(onRetry: () => ref.invalidate(orderListProvider)),
      data: (orders) => _OrderListView(orders: orders),
    );
  }
}