feat: update user sync terminology for clarity in English and Chinese

ui/src/locales/lang/en-US/views/chat-user.ts

@@ -1,7 +1,7 @@
 export default {
   title: 'Chat Users',
-  syncUsers: 'Sync Users',
-  syncUsersTip: 'Only sync newly added users',
+  syncUsers: 'Import Users',
+  syncUsersTip: 'Only import newly added users',
   setUserGroups: 'Configure User Groups',
   knowledgeTitleTip:
     'This configuration will only take effect after enabling chat user login authentication in the associated application',

ui/src/locales/lang/zh-CN/views/chat-user.ts

@@ -1,7 +1,7 @@
 export default {
   title: '对话用户',
-  syncUsers: '同步用户',
-  syncUsersTip: '仅同步新增用户',
+  syncUsers: '导入用户',
+  syncUsersTip: '仅导入新增用户',
   setUserGroups: '设置用户组',
   knowledgeTitleTip: '该配置需要关联的应用开启对话用户登录认证后才会生效',
   applicationTitleTip: '该配置需要应用开启登录认证后生效',

ui/src/locales/lang/zh-Hant/views/chat-user.ts

@@ -1,7 +1,7 @@
 export default {
   title: '對話用戶',
-  syncUsers: '同步用戶',
-  syncUsersTip: '僅同步新增用戶',
+  syncUsers: '导入用戶',
+  syncUsersTip: '僅导入新增用戶',
   setUserGroups: '設定用戶組',
   knowledgeTitleTip: '該配置需要關聯的應用開啟對話用戶登入認證後才會生效',
   applicationTitleTip: '該配置需要應用開啟登入認證後生效',