fix: 将birthday字段重命名为birth_date以保持一致性

 <!--
  * @Date: 2025-08-27 17:43:45
  * @LastEditors: hookehuyr hookehuyr@gmail.com
- * @LastEditTime: 2025-09-26 17:27:40
+ * @LastEditTime: 2025-09-27 16:09:23
  * @FilePath: /lls_program/src/pages/Welcome/index.vue
  * @Description: 欢迎页
 -->
@@ -204,7 +204,7 @@ useDidShow(async () => {
     userInfo.value = data?.user?.nickname ? data.user : {
       avatar_url: null,
       nickname: null,
-      birthday: null,
+      birth_date: null,
       wheelchair: null,
       wheelchair_text: null,
       phone: null,