tentatively shrink trip overview, nicer onboarding

frontend/lib/pages/base_page.dart

@@ -1,3 +1,4 @@
+import 'package:anyway/main.dart';
 import 'package:anyway/modules/help_dialog.dart';
 import 'package:anyway/pages/current_trip.dart';
 import 'package:anyway/pages/settings.dart';
@@ -38,7 +39,8 @@ class _BasePageState extends State<BasePage> {
 
   @override
   Widget build(BuildContext context) {
-    Future<List<Trip>> trips = loadTrips();
+    savedTrips.loadTrips();
+
 
     return Scaffold(
       appBar: AppBar(
@@ -98,11 +100,11 @@ class _BasePageState extends State<BasePage> {
             // through the options in the drawer if there isn't enough vertical
             // space to fit everything.
             Expanded(
-              child: TripsOverview(trips: trips),
+              child: TripsOverview(trips: savedTrips),
             ),
             ElevatedButton(
               onPressed: () async {
-                removeAllTripsFromPrefs();
+                savedTrips.clearTrips();
               },
               child: const Text('Clear trips'),
             ),