new settings panel for url pickup

lib/services/endpoint_service.dart

@@ -0,0 +1,36 @@
+import 'package:flutter/foundation.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+class EndpointService extends ChangeNotifier {
+  EndpointService() {
+    _load();
+  }
+
+  static const String defaultBaseUrl = 'https://mileograph.co.uk/api/v1';
+  static const String _prefsKey = 'api_base_url';
+
+  String _baseUrl = defaultBaseUrl;
+  bool _loaded = false;
+
+  String get baseUrl => _baseUrl;
+  bool get isLoaded => _loaded;
+
+  Future<void> _load() async {
+    final prefs = await SharedPreferences.getInstance();
+    final saved = prefs.getString(_prefsKey);
+    if (saved != null && saved.trim().isNotEmpty) {
+      _baseUrl = saved;
+    }
+    _loaded = true;
+    notifyListeners();
+  }
+
+  Future<void> setBaseUrl(String url) async {
+    final trimmed = url.trim();
+    if (trimmed.isEmpty) return;
+    _baseUrl = trimmed;
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.setString(_prefsKey, _baseUrl);
+    notifyListeners();
+  }
+}