Add option to save the preference for viewing large icons

lib/services/preference_service.dart

@@ -8,6 +8,7 @@ class PreferenceService {
   late final SharedPreferences _prefs;
 
   static const kHasShownCoachMarkKey = "has_shown_coach_mark";
+  static const kShouldShowLargeIconsKey = "should_show_large_icons";
 
   Future<void> init() async {
     _prefs = await SharedPreferences.getInstance();
@@ -24,4 +25,16 @@ class PreferenceService {
   Future<void> setHasShownCoachMark(bool value) {
     return _prefs.setBool(kHasShownCoachMarkKey, value);
   }
+
+  bool shouldShowLargeIcons() {
+    if (_prefs.containsKey(kShouldShowLargeIconsKey)) {
+      return _prefs.getBool(kShouldShowLargeIconsKey)!;
+    } else {
+      return false;
+    }
+  }
+
+  Future<void> setShowLargeIcons(bool value) {
+    return _prefs.setBool(kShouldShowLargeIconsKey, value);
+  }
 }