fix: some warnings remove + light / ugly theme added

lib/app/app.dart

@@ -1,7 +1,10 @@
 import 'package:flutter/material.dart';
 import 'package:go_router/go_router.dart';
-import 'package:kooltab2/theme.dart';
-import 'package:kooltab2/utils/app_update_util.dart';
+import 'package:provider/provider.dart';
+
+import '../models/settings.dart';
+import '../viewmodels/settings_view_model.dart';
+import '../theme.dart';
 
 class KoolTabApp extends StatefulWidget {
   const KoolTabApp({super.key, required this.router});
@@ -13,13 +16,37 @@ class KoolTabApp extends StatefulWidget {
 }
 
 class _KoolTabAppState extends State<KoolTabApp> {
+  @override
+  void initState() {
+    super.initState();
+
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      context.read<SettingsViewModel>().ensureLoaded();
+    });
+  }
+
   @override
   Widget build(BuildContext context) {
+    final settings = context.watch<SettingsViewModel>().settings;
+
     return MaterialApp.router(
       title: 'KoolTab',
       debugShowCheckedModeBanner: false,
       routerConfig: widget.router,
-      theme: darkTheme,
+      theme: lightTheme,
+      darkTheme: darkTheme,
+      themeMode: _mapThemeMode(settings.themeMode, context),
     );
   }
-}
+
+  ThemeMode _mapThemeMode(AppThemeMode mode, BuildContext context) {
+    final hasLoaded = context.read<SettingsViewModel>().hasLoaded;
+
+    return switch (mode) {
+      AppThemeMode.dark => ThemeMode.dark,
+      AppThemeMode.light => ThemeMode.light,
+      AppThemeMode.system =>
+        hasLoaded ? ThemeMode.system : ThemeMode.dark,
+    };
+  }
+}