feat(theme): Добавить ThemeExtension для токенов цвета (#12)

* feat
* fix
* fix: исправил ширину строки
* feat: добавить визуальный элемент

lib/features/debug/screens/lang_screen.dart

@@ -1,6 +1,5 @@
 import 'package:flutter/material.dart';
 import 'package:friflex_starter/app/app_context_ext.dart';
-import 'package:friflex_starter/app/theme/app_colors_scheme.dart';
 import 'package:friflex_starter/gen/assets.gen.dart';
 import 'package:friflex_starter/gen/fonts.gen.dart';
 

lib/features/debug/screens/theme_screen.dart

@@ -1,6 +1,5 @@
 import 'package:flutter/material.dart';
 import 'package:friflex_starter/app/app_context_ext.dart';
-import 'package:friflex_starter/app/theme/app_colors_scheme.dart';
 
 /// {@template ThemeScreen}
 ///  Экран для отладки темы приложения
@@ -11,6 +10,7 @@ class ThemeScreen extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
+    final colors = context.colors;
     return Scaffold(
       appBar: AppBar(title: const Text('Theme')),
       body: Center(
@@ -29,7 +29,25 @@ class ThemeScreen extends StatelessWidget {
               child: const SizedBox(height: 100, width: 100),
             ),
             const SizedBox(height: 16),
-            Text('Текущая тема: ${context.theme.themeMode}'),
+            Card(
+              elevation: 4,
+              shadowColor: colors.infoSnackbarBackground,
+              margin: const EdgeInsets.symmetric(vertical: 10),
+              color: colors.infoSnackbarBackground,
+              shape: RoundedRectangleBorder(
+                borderRadius: BorderRadius.circular(16),
+              ),
+              child: ListTile(
+                title: Text(
+                  'Текущая тема: ${context.theme.themeMode}',
+                  style: TextStyle(
+                    color: colors.itemTextColor,
+                    fontWeight: FontWeight.bold,
+                  ),
+                ),
+                trailing: Icon(Icons.color_lens, color: colors.itemTextColor),
+              ),
+            ),
           ],
         ),
       ),