update

lib/features/settings/provider.dart

@@ -0,0 +1,18 @@
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import '../dashboard/provider.dart';
+
+final budgetProvider = StateNotifierProvider<BudgetNotifier, double?>((ref) {
+  final storage = ref.watch(storageServiceProvider);
+  return BudgetNotifier(storage.loadBudget(), storage);
+});
+
+class BudgetNotifier extends StateNotifier<double?> {
+  final dynamic _storage;
+
+  BudgetNotifier(super.initialBudget, this._storage);
+
+  Future<void> setBudget(double? budget) async {
+    await _storage.saveBudget(budget);
+    state = budget;
+  }
+}