feat(): add snackbar on click on toggle favorite

lib/screens/tabs.dart

@@ -15,6 +15,12 @@ class _TabsScreenState extends State<TabsScreen> {
   int _selectedPageIndex = 0;
   final List<Meal> _favoriteMeals = [];
 
+  void _showInfoMessage(String message) {
+    ScaffoldMessenger.of(context).clearSnackBars();
+    ScaffoldMessenger.of(context)
+        .showSnackBar(SnackBar(content: Text(message)));
+  }
+
   void _selectPage(int index) {
     setState(() {
       _selectedPageIndex = index;
@@ -26,9 +32,11 @@ class _TabsScreenState extends State<TabsScreen> {
       setState(() {
         _favoriteMeals.remove(meal);
       });
+      _showInfoMessage('Meal is no longer a favorite');
     } else {
       setState(() {
         _favoriteMeals.add(meal);
+        _showInfoMessage('Meal has been added to your favorites');
       });
     }
   }