fix(mail): 修复 vue-tsc -b 构建类型错误（表格行类型断言与残留导入）

Mailbox/MailAdmin 模板内 DefaultRow 类型断言为 JmapEmail/MailAdminItem，清理无用 dateNow 与 buildBasicToken 残留引用

src/views/mail/MailAdmin.vue

@@ -75,7 +75,7 @@ async function disable(row: MailAdminItem): Promise<void> {
         </el-table-column>
         <el-table-column label="操作" width="100" align="center">
           <template #default="{ row }">
-            <el-button v-if="row.Status === 1" text type="danger" size="small" @click="disable(row)">禁用</el-button>
+            <el-button v-if="row.Status === 1" text type="danger" size="small" @click="disable(row as MailAdminItem)">禁用</el-button>
             <span v-else class="disabled-text">已禁用</span>
           </template>
         </el-table-column>

src/views/mail/Mailbox.vue

@@ -16,7 +16,7 @@
 import { ref, computed, onMounted, nextTick } from 'vue'
 import { ElMessage, ElMessageBox } from 'element-plus'
 import { mailApi, type MailboxInfo, type MailSessionConfig } from '@/api/mail'
-import { JmapClient, buildBasicToken, type JmapMailbox, type JmapEmail } from '@/utils/jmap'
+import { JmapClient, type JmapMailbox, type JmapEmail } from '@/utils/jmap'
 
 // === 状态 ===
 
@@ -274,8 +274,6 @@ const emailBodyText = computed(() => {
   return '(无正文内容)'
 })
 
-const dateNow = Date.now()
-
 // 打开邮箱详情页时挂载邮箱列表
 async function openMailbox(): Promise<void> {
   loginVisible.value = true
@@ -330,7 +328,7 @@ async function openMailbox(): Promise<void> {
           <el-button text type="danger" @click="logoutMail">退出邮箱</el-button>
         </div>
 
-        <el-table v-loading="emailsLoading" :data="emails" class="email-table" @row-click="(row: JmapEmail) => openDetail(row)">
+        <el-table v-loading="emailsLoading" :data="emails" class="email-table" @row-click="(row: any) => openDetail(row as JmapEmail)">
           <el-table-column width="50">
             <template #default="{ row }">
               <span v-if="!row.keywords?.$seen" class="unread-dot" />
@@ -338,7 +336,7 @@ async function openMailbox(): Promise<void> {
           </el-table-column>
           <el-table-column prop="from" :width="260">
             <template #default="{ row }">
-              <span :class="{ 'unread-text': !row.keywords?.$seen }">{{ formatSender(row) }}</span>
+              <span :class="{ 'unread-text': !row.keywords?.$seen }">{{ formatSender(row as JmapEmail) }}</span>
             </template>
           </el-table-column>
           <el-table-column prop="subject" min-width="240">
@@ -353,7 +351,7 @@ async function openMailbox(): Promise<void> {
             <template #default="{ row }">
               <div class="email-date">
                 <span>{{ formatDate(row.receivedAt || row.date) }}</span>
-                <el-button text type="danger" size="small" @click.stop="deleteEmail(row)">删除</el-button>
+                <el-button text type="danger" size="small" @click.stop="deleteEmail(row as JmapEmail)">删除</el-button>
               </div>
             </template>
           </el-table-column>