fix: Fix lint issues in widget tests

- Add const to MaterialApp constructors
- Remove const from localizationsDelegates array
- All analyzer issues resolved

Author: aimuhire

mobile/test/widget_test.dart

@@ -41,22 +41,23 @@ void main() {
             ChangeNotifierProvider(create: (_) => SettingsProvider(prefs)),
             ChangeNotifierProvider(create: (_) => ServerStatusProvider()),
           ],
-          child: MaterialApp(
-            localizationsDelegates: const [
+          child: const MaterialApp(
+            localizationsDelegates: [
               AppLocalizations.delegate,
               GlobalMaterialLocalizations.delegate,
               GlobalWidgetsLocalizations.delegate,
               GlobalCupertinoLocalizations.delegate,
             ],
             supportedLocales: AppLocalizations.supportedLocales,
-            home: const HomeScreen(),
+            home: HomeScreen(),
           ),
         ),
       );
 
       // Verify that the home screen displays
       expect(find.text('Paste Link to Clean'), findsOneWidget);
-      expect(find.text('TraceOff — Clean Links'), findsOneWidget); // App bar title
+      expect(
+          find.text('TraceOff — Clean Links'), findsOneWidget); // App bar title
     });
 
     testWidgets('URL input field accepts text', (WidgetTester tester) async {
@@ -71,15 +72,15 @@ void main() {
             ChangeNotifierProvider(create: (_) => SettingsProvider(prefs)),
             ChangeNotifierProvider(create: (_) => ServerStatusProvider()),
           ],
-          child: MaterialApp(
-            localizationsDelegates: const [
+          child: const MaterialApp(
+            localizationsDelegates: [
               AppLocalizations.delegate,
               GlobalMaterialLocalizations.delegate,
               GlobalWidgetsLocalizations.delegate,
               GlobalCupertinoLocalizations.delegate,
             ],
             supportedLocales: AppLocalizations.supportedLocales,
-            home: const HomeScreen(),
+            home: HomeScreen(),
           ),
         ),
       );
@@ -108,15 +109,15 @@ void main() {
             ChangeNotifierProvider(create: (_) => SettingsProvider(prefs)),
             ChangeNotifierProvider(create: (_) => ServerStatusProvider()),
           ],
-          child: MaterialApp(
-            localizationsDelegates: const [
+          child: const MaterialApp(
+            localizationsDelegates: [
               AppLocalizations.delegate,
               GlobalMaterialLocalizations.delegate,
               GlobalWidgetsLocalizations.delegate,
               GlobalCupertinoLocalizations.delegate,
             ],
             supportedLocales: AppLocalizations.supportedLocales,
-            home: const HomeScreen(),
+            home: HomeScreen(),
           ),
         ),
       );
@@ -139,7 +140,7 @@ void main() {
       // Verify the text was entered (the field should accept any text)
       // Note: The text might be formatted differently in the TextField
       expect(find.byType(TextField), findsOneWidget);
-      
+
       // Verify that the TextField contains the URL we entered
       final textField = tester.widget<TextField>(find.byType(TextField));
       expect(textField.controller?.text, contains('https://gboard.app.goo.gl'));