fix theme / add history

lib/viewmodels/history_view_model.dart

@@ -0,0 +1,62 @@
+import 'package:flutter/foundation.dart';
+
+import '../models/closed_tab.dart';
+import '../services/bar_tab_service.dart';
+
+class HistoryViewModel extends ChangeNotifier {
+  final BarTabService barTabService;
+
+  HistoryViewModel({
+    required this.barTabService,
+  });
+
+  List<ClosedTab> _closedTabs = [];
+  bool _isLoading = false;
+  bool _hasLoaded = false;
+  String? _errorMessage;
+  String _searchQuery = '';
+
+  List<ClosedTab> get closedTabs {
+    if (_searchQuery.isEmpty) return _closedTabs;
+
+    return _closedTabs
+        .where((tab) =>
+        tab.customerName.toLowerCase().contains(_searchQuery.toLowerCase()))
+        .toList();
+  }
+
+  bool get isLoading => _isLoading;
+
+  bool get hasLoaded => _hasLoaded;
+
+  String? get errorMessage => _errorMessage;
+
+  Future<void> ensureLoaded() async {
+    if (_hasLoaded || _isLoading) return;
+
+    await load();
+  }
+
+  Future<void> load() async {
+    if (_isLoading) return;
+
+    _isLoading = true;
+    _errorMessage = null;
+    notifyListeners();
+
+    try {
+      _closedTabs = await barTabService.getClosedTabs();
+    } catch (_) {
+      _errorMessage = 'Could not load tab history.';
+    } finally {
+      _hasLoaded = true;
+      _isLoading = false;
+      notifyListeners();
+    }
+  }
+
+  void search(String query) {
+    _searchQuery = query;
+    notifyListeners();
+  }
+}