Features: 1) Add support for small_logo and big_logo in admin display;

Fixes: 1) Remove deprecated relation_fields;

Extra: 1) Refactor field definitions for clarity and consistency.

engine/core/admin.py

@@ -375,7 +375,6 @@ class BrandAdmin(DjangoQLSearchMixin, FieldsetsMixin, ActivationActionsMixin, Mo
     search_fields = (
         "uuid",
         "name",
-        "categories__name",
     )
     readonly_fields = (
         "uuid",
@@ -389,9 +388,10 @@ class BrandAdmin(DjangoQLSearchMixin, FieldsetsMixin, ActivationActionsMixin, Mo
         "description",
         "priority",
     ]
-    relation_fields = [
-        "categories",
-    ]
+    additional_fields = [
+        "small_logo",
+        "big_logo"
+        ]
 
 
 @register(Product)