fix(auth): 更新消息标识符并调整预览样式

public/test-host.html

@@ -34,7 +34,7 @@
         }
 
         .preview {
-            width: 500px;
+            width: 100%;
             height: 800px;
             overflow: auto;
         }

src/features/authGuide.tsx

@@ -9,8 +9,8 @@ import {queryKeys} from '@/lib/queryKeys.ts'
 import {useUserStore} from '@/store/user.ts'
 import type {HostContextMessage} from '@/types'
 
-const HOST_READY_MESSAGE = 'PLAYX_READY'
-const HOST_HEIGHT_MESSAGE = 'PLAYX_HEIGHT'
+const HOST_READY_MESSAGE = 'IFRAME_READY'
+const HOST_HEIGHT_MESSAGE = 'IFRAME_HEIGHT'
 const HOST_READY_INTERVAL = 500
 const HOST_READY_RETRY_LIMIT = 20
 const HOST_HEIGHT_REPORT_INTERVAL = 250