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/CourseAdjustmentsView.vue

@@ -3,6 +3,7 @@ import { computed, onMounted, reactive, ref } from 'vue'
 import { Bell, Check, Plus, Refresh } 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(() =>
@@ -172,7 +173,7 @@ onMounted(async () => {
     ])
     terms.value = termRes.data
     tasks.value = taskRes.data.items
-    termId.value = terms.value.find(t => t.isCurrent)?.id
+    termId.value = defaultAcademicTermId(terms.value)
   } catch (_) {}
   await load()
 })
@@ -204,7 +205,7 @@ function showCancel(type: string) { return type === 'Cancel' }
 
     <section class="adj-toolbar">
       <el-select v-model="termId" clearable placeholder="全部学期" @change="load">
-        <el-option v-for="t in terms" :key="t.id" :label="t.name" :value="t.id" />
+        <el-option v-for="t in terms" :key="t.id" :label="academicTermLabel(t)" :value="t.id" :class="academicTermOptionClass(t)" />
       </el-select>
       <el-segmented v-model="tab" :options="[
         ...(isTeacher ? [{ label: '我的申请', value: 'mine' }] : []),