学年学期页面新增“设为当前”“归档”“撤销归档”，当前学期不能归档、删除或直接取消；已归档学期需先撤销才能重新设为当前。[BaseDataController.cs (line 286)](/E:/jiaowu/src/Jiaowu.Api/Controllers/BaseDataController.cs:286)

切换后，其他学期自动变为历史态；已归档学期进一步弱化。所有主要学期选择器统一默认当前，并显示“当前 / 历史 / 已归档”。[academicTerms.ts (line 1)](/E:/jiaowu/web/src/utils/academicTerms.ts:1)
桌面使用分层表格，390px 手机端改为独立学期卡片，操作不会再挤压表格。[BaseDataView.vue (line 211)](/E:/jiaowu/web/src/views/BaseDataView.vue:211)
归档定义为“历史显示状态”，不是成绩冻结：补考成绩仍可录入并回写，已发布成绩仍可走成绩更正审批。
已加入 SQLite 开发迁移、MySQL 正式迁移和切换/归档/撤销测试。[20260726143000_AcademicTermArchiving.cs (line 1)](/E:/jiaowu/src/Jiaowu.Api/Infrastructure/Persistence/Migrations/MySql/20260726143000_AcademicTermArchiving.cs:1)

web/src/views/GradesView.vue

@@ -14,6 +14,7 @@ import {
 import http, { apiErrorMessage } from '../api/http'
 import { downloadApiFile, importExcel } from '../api/excel'
 import { useAuthStore } from '../stores/auth'
+import { academicTermLabel, academicTermOptionClass, defaultAcademicTermId } from '../utils/academicTerms'
 
 const auth = useAuthStore()
 const isStudent = computed(() => auth.user?.roles.includes('Student') &&
@@ -351,7 +352,7 @@ function calcPreviewTotal(record: any): number | null {
 onMounted(async () => {
   try {
     terms.value = (await http.get('/base-data/terms')).data
-    termId.value = terms.value.find((item) => item.isCurrent)?.id
+    termId.value = defaultAcademicTermId(terms.value)
     await load()
   } catch (error) {
     ElMessage.error(apiErrorMessage(error))
@@ -381,7 +382,7 @@ onMounted(async () => {
         <label>
           <span>查看学期</span>
           <el-select v-model="termId" clearable placeholder="全部学期" @change="load">
-            <el-option v-for="term in terms" :key="term.id" :label="term.name" :value="term.id" />
+            <el-option v-for="term in terms" :key="term.id" :label="academicTermLabel(term)" :value="term.id" :class="academicTermOptionClass(term)" />
           </el-select>
         </label>
       </section>
@@ -421,7 +422,7 @@ onMounted(async () => {
     <template v-else>
       <section class="grade-toolbar">
         <el-select v-model="termId" clearable placeholder="全部学期" @change="load">
-          <el-option v-for="term in terms" :key="term.id" :label="term.name" :value="term.id" />
+          <el-option v-for="term in terms" :key="term.id" :label="academicTermLabel(term)" :value="term.id" :class="academicTermOptionClass(term)" />
         </el-select>
         <el-select v-model="status" clearable placeholder="全部状态" @change="load">
           <el-option v-for="(label, value) in statusLabels" :key="value" :label="label" :value="value" />