fix: long navigation menu can be scrolled

* 修复超长的导航菜单无法纵向滚动的问题

Author: mynetfan

packages/@core/ui-kit/menu-ui/src/components/sub-menu.vue

@@ -208,6 +208,8 @@ onBeforeUnmount(() => {
           nsMenu.e('popup-container'),
           is(rootMenu.theme, true),
           opened ? '' : 'hidden',
+          'overflow-auto',
+          'max-h-[calc(var(--radix-hover-card-content-available-height)-20px)]',
         ]"
         :content-props="contentProps"
         :open="true"