Get element by key won't work with keyComparator

**Question**
Once I open a box using `keyComparator` functions like `Hive.box(shoppingListBox).get(id)` and `Hive.box(shoppingListBox).containsKey(id)` won't work.
After removing `keyComparator` when opening a box it works fine.

**Code sample**
```dart
const shoppingListBox = 'shoppingListBox';

await Hive.openBox(shoppingListBox, keyComparator: (a, b) => -1); //DESC order

final id = const Uuid().v4();
await Hive.box(shoppingListBox).put(id, ShoppingList('Item name', [], DateTime.now()));

final shoppingList = Hive.box(shoppingListBox).get(id); //returns null
final shoppingListExists = Hive.box(shoppingListBox).containsKey(id); //returns false

//shopping_list.dart
@HiveType(typeId: 0)
class ShoppingList extends HiveObject {
@HiveField(0)
String name;

@HiveField(1)
List products;

@HiveField(2)
DateTime? dateAdded;

ShoppingList(this.name, this.products, this.dateAdded);
}
```

**Version**
- Platform: Mac
- Flutter version: 3.0.4
- Hive version: 2.2.3

Reproduce the sample with Hive.openBox using keyComparator, then exercise Box.get and Box.containsKey with the inserted key. Trace the lookup path from those entry points; done means both lookups return the inserted ShoppingList while the comparator is enabled, with regression coverage for each call.

Written by the indexing model from the issue text.