fix: reformat code / code improvements

lib/models/bar_tab.dart

@@ -1,4 +1,5 @@
 import 'tab_item.dart';
+import '../utils/collection_utils.dart';
 
 class BarTab {
   final String id;
@@ -40,7 +41,7 @@ class BarTab {
           status == other.status &&
           openedAt == other.openedAt &&
           closedAt == other.closedAt &&
-          _listEquals(items, other.items);
+          listEquals(items, other.items);
 
   @override
   int get hashCode => Object.hash(
@@ -53,12 +54,4 @@ class BarTab {
       );
 }
 
-bool _listEquals<T>(List<T>? a, List<T>? b) {
-  if (identical(a, b)) return true;
-  if (a == null || b == null) return a == b;
-  if (a.length != b.length) return false;
-  for (int i = 0; i < a.length; i++) {
-    if (a[i] != b[i]) return false;
-  }
-  return true;
-}
+// _listEquals moved to utils/collection_utils.dart