feat(profile): refine student creation workflow

pages/defaults/index.ts

@@ -1,11 +1,11 @@
 import { getApiErrorMessage, getProfileDefaults, updateProfileDefaults } from '../../utils/api'
 import type { StudentProfileDefaults } from '../../utils/types'
 
-const grades = ['艺术类', '幼儿园', '一年级', '二年级', '三年级', '四年级', '五年级', '六年级']
+const grades = ['初一', '初二', '初三']
 const subjects = ['美术', '书法', '音乐', '舞蹈', '语文', '数学', '英语']
 const initialDefaults: StudentProfileDefaults = {
-  grade: '艺术类',
-  subject: '美术',
+  grade: '初一',
+  subject: '数学',
   lessonDurationMinutes: 60
 }