added base homescreen-widget setup, working on Android, iOS in progress

lib/widget_data/widget_navigation.dart

@@ -0,0 +1,24 @@
+import 'dart:developer';
+
+import 'package:flutter/services.dart';
+
+/// Android-only bridge: MainActivity stashes `widget_open_timetable=true`
+/// from the launch Intent extra when a widget is tapped, Dart polls once
+/// per app-resume to consume and route. iOS widgets simply launch the app
+/// without a navigation hint (no widgetURL set) so this returns `false`
+/// there via MissingPluginException.
+class WidgetNavigation {
+  static const MethodChannel _channel = MethodChannel('eu.mhsl.marianum.widget');
+
+  static Future<bool> consumePendingTimetableTap() async {
+    try {
+      final raw = await _channel.invokeMethod<bool>('consumePendingNavigation');
+      return raw ?? false;
+    } on MissingPluginException {
+      return false;
+    } on PlatformException catch (e) {
+      log('WidgetNavigation channel error: $e');
+      return false;
+    }
+  }
+}