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/ExamsView.vue

@@ -3,6 +3,7 @@ import { computed, onMounted, reactive, ref } from 'vue'
 import { Plus, Promotion, Refresh, UserFilled, Setting } from '@element-plus/icons-vue'
 import http, { apiErrorMessage } from '../api/http'
 import { useAuthStore } from '../stores/auth'
+import { academicTermLabel, academicTermOptionClass, defaultAcademicTermId } from '../utils/academicTerms'
 
 const auth = useAuthStore()
 const isManager = computed(() =>
@@ -53,7 +54,9 @@ async function load() {
       return
     }
     plans.value = (await http.get('/exams/plans')).data
-    const plan = plans.value.find((x) => x.id === selected.value?.id) ?? plans.value[0]
+    const plan = plans.value.find((x) => x.id === selected.value?.id)
+      ?? plans.value.find((x) => x.termIsCurrent)
+      ?? plans.value[0]
     if (plan) await selectPlan(plan.id)
   } catch (error) { ElMessage.error(apiErrorMessage(error)) }
   finally { loading.value = false }
@@ -63,7 +66,7 @@ async function selectPlan(id: string) {
 }
 function openPlan() {
   Object.assign(planForm, {
-    academicTermId: terms.value.find((x) => x.isCurrent)?.id,
+    academicTermId: defaultAcademicTermId(terms.value),
     name: '', notes: '',
   })
   planDialog.value = true
@@ -196,7 +199,7 @@ onMounted(async () => {
 
     <template v-if="isManager">
       <section class="exam-plan-strip">
-        <button v-for="plan in plans" :key="plan.id" :class="{ active: selected?.id === plan.id }" @click="selectPlan(plan.id)">
+        <button v-for="plan in plans" :key="plan.id" :class="{ active: selected?.id === plan.id, 'historical-record': !plan.termIsCurrent && !plan.termIsArchived, 'archived-record': plan.termIsArchived }" @click="selectPlan(plan.id)">
           <span>{{ plan.termName }}</span><b>{{ plan.name }}</b>
           <small>{{ plan.sessionCount }} 个场次</small><i>{{ statusLabels[plan.status] }}</i>
         </button>
@@ -271,7 +274,7 @@ onMounted(async () => {
       <el-form label-position="top">
         <el-form-item label="学期">
           <el-select v-model="planForm.academicTermId">
-            <el-option v-for="x in terms" :key="x.id" :label="x.name" :value="x.id" />
+            <el-option v-for="x in terms" :key="x.id" :label="academicTermLabel(x)" :value="x.id" :class="academicTermOptionClass(x)" />
           </el-select>
         </el-form-item>
         <el-form-item label="计划名称"><el-input v-model="planForm.name" maxlength="120" /></el-form-item>