Frontend first draft

frontend/pweb/lib/providers/template.dart

@@ -0,0 +1,31 @@
+import 'package:flutter/material.dart';
+
+
+class FutureProviderTemplate<T> extends ChangeNotifier {
+  FutureProviderTemplate({required this.loader});
+
+  final Future<T> Function() loader;
+
+  T? _data;
+  bool _isLoading = false;
+  String? _error;
+
+  T? get data => _data;
+  bool get isLoading => _isLoading;
+  String? get error => _error;
+
+  Future<void> load() async {
+    _isLoading = true;
+    _error = null;
+    notifyListeners();
+
+    try {
+      _data = await loader();
+    } catch (e) {
+      _error = e.toString();
+    }
+
+    _isLoading = false;
+    notifyListeners();
+  }
+}