优化消息XML内容，提取到静态文件里面。

plugins/group_member_change/main.py

@@ -10,6 +10,7 @@ from db.contacts_db import ContactsDBOperator
 from utils.robot_cmd.robot_command import Feature, PermissionStatus, GroupBotManager
 from utils.wechat.contact_manager import ContactManager
 from wechat_ipad import WechatAPIClient
+from wechat_ipad.models.appmsg_xml import LINK_XML
 
 
 class GroupMemberChangePlugin(MessagePluginInterface):
@@ -134,53 +135,8 @@ class GroupMemberChangePlugin(MessagePluginInterface):
                     contact_db.save_chatroom_member_simple(roomid, member_details)
                 except Exception as e:
                     self.LOG.warning(f"新增群员信息失败: {e}")
-                xml_content = f"""
-<appmsg appid="" sdkver="1">
-		<title>👏欢迎 {nickname} 加入群聊！🎉</title>
-		<des>⌚时间：{now}</des>
-		<action>view</action>
-		<type>5</type>
-		<showtype>0</showtype>
-		<content />
-		<url>https://hot.imsyy.top/#/</url>
-		<dataurl />
-		<lowurl />
-		<lowdataurl />
-		<recorditem />
-		<thumburl>{head_url}</thumburl>
-		<messageaction />
-		<laninfo />
-		<extinfo />
-		<sourceusername />
-		<sourcedisplayname />
-		<commenturl />
-		<appattach>
-			<totallen>0</totallen>
-			<attachid />
-			<emoticonmd5 />
-			<fileext />
-			<aeskey />
-		</appattach>
-		<webviewshared>
-			<publisherId />
-			<publisherReqId>0</publisherReqId>
-		</webviewshared>
-		<weappinfo>
-			<pagepath />
-			<username />
-			<appid />
-			<appservicetype>0</appservicetype>
-		</weappinfo>
-		<websearch />
-	</appmsg>
-	<fromusername>Jyunere</fromusername>
-	<scene>0</scene>
-	<appinfo>
-		<version>1</version>
-		<appname></appname>
-	</appinfo>
-	<commenturl></commenturl>
-	"""
+                xml_content = f"{LINK_XML}".format(nickname=nickname, now=now, head_url=head_url)
+
                 await bot.send_link_xml_message(xml_content, roomid)
                 return True, "已发送进群欢迎语"
         return False, "无需执行"