补充视图消息服务继承基类

APP/src/message/%APP_MSG%/%APP_MSG%-message-base.ts.ftl

 <#ibiztemplate>
 TARGET=PSAPPVIEWMSG
 </#ibiztemplate>
+import ViewMessageService from '../view-message-service';
 /**
  * ${item.getName()}视图消息服务对象基类
  *
  * @export
  * @class ${item.getCodeName()}MessageServiceBase
  */
-export default class ${srfclassname('${item.getCodeName()}')}MessageServiceBase {
+export default class ${srfclassname('${item.getCodeName()}')}MessageServiceBase extends ViewMessageService {
 
     /**
      * Creates an instance of  ${srfclassname('${item.getCodeName()}')}MessageServiceBase.