fix(system): 修复修改菜单时父级菜单选择为当前菜单的问题

- 在修改菜单时增加了一个判断，如果父级菜单 ID与当前菜单 ID 相同，则抛出异常
- 异常信息为 "父级菜单不能为当前菜单"，避免了逻辑上的错误

src/main/java/com/youlai/boot/system/service/impl/MenuServiceImpl.java

@@ -241,7 +241,9 @@ public class MenuServiceImpl extends ServiceImpl<MenuMapper, Menu> implements Me
 
             menuForm.setComponent(null);
         }
-
+        if (Objects.equals(menuForm.getParentId(), menuForm.getId())){
+            throw new RuntimeException("父级菜单不能为当前菜单");
+        }
         Menu entity = menuConverter.toEntity(menuForm);
         String treePath = generateMenuTreePath(menuForm.getParentId());
         entity.setTreePath(treePath);