优化粘贴提示；优化菜单导入清空缓存

extend/base/admin/controller/system/MenuBase.php

@@ -276,6 +276,7 @@ class MenuBase extends AdminController
                 Db::rollback();
                 $this->error('导入失败:' . $th->getMessage());
             }
+            TriggerService::updateMenu();
             $this->success('导入成功');
         }
 

public/static/plugs/ulthon-admin/ulthon-admin.js

@@ -2438,6 +2438,10 @@
 
                     var targetElemName = $(v).data('paste-target');
                     $(v).on('click', function () {
+                        if(!navigator.clipboard){
+                            admin.msg.error('您的当前不支持粘贴操作');
+                            return;
+                        }
                         navigator.clipboard.readText()
                             .then(text => {
                                 $(targetElemName).val(text);