Added: user settings screen, Several changes in main.lib

lib/main.dart

@@ -3,6 +3,7 @@ import 'screens/home_screen.dart';
 import 'screens/add_screen.dart';
 import 'screens/vehicles_screen.dart';
 import 'screens/history_screen.dart';
+import 'screens/user_settings.dart';
 
 void main() {
   runApp(FuelStatsApp());
@@ -12,9 +13,9 @@ class FuelStatsApp extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     return MaterialApp(
-      title: 'Fuel Stats',
       theme: ThemeData.dark(),
       themeMode: ThemeMode.dark,
+      debugShowCheckedModeBanner: false,
       home: MainNavigation(),
     );
   }
@@ -35,20 +36,42 @@ class _MainNavigationState extends State<MainNavigation> {
     AddScreen(),
     VehiclesScreen(),
     HistoryScreen(),
+    UserSettingsScreen(),
+  ];
+
+  final List<Widget> titles = [
+    Text("Fuel Stats"),
+    Text("Add record"),
+    Text("Vehicles"),
+    Text("History"),
   ];
 
   @override
   Widget build(BuildContext context) {
     return Scaffold(
+      appBar: AppBar(
+        title: _currentIndex <= 3 ? titles[_currentIndex] : Text("Fuel Stats"),
+        actions: [
+          IconButton(
+            icon: const Icon(Icons.person),
+            tooltip: "User settings",
+            onPressed: () {
+              Navigator.push(
+                context,
+                MaterialPageRoute(builder: (context) => UserSettingsScreen()),
+              );
+            },
+          ),
+        ],
+      ),
       body: _screens[_currentIndex],
       bottomNavigationBar: BottomNavigationBar(
-        currentIndex: _currentIndex,
+        currentIndex: _currentIndex <= 3 ? _currentIndex : 0,
         onTap: (index) => setState(() => _currentIndex = index),
         backgroundColor: Colors.grey[900],
         selectedItemColor: Colors.white,
         unselectedItemColor: Colors.grey,
-
-        items: [
+        items: const [
           BottomNavigationBarItem(icon: Icon(Icons.home), label: 'Home'),
           BottomNavigationBarItem(icon: Icon(Icons.add), label: 'Add'),
           BottomNavigationBarItem(