feat: PDF 页签删除任务去掉二次确认弹窗

用户页签删除任务为软删（管理员仍可见，可恢复），误操作代价低，二次确认徒增摩擦。
点击删除直接执行，与「下载」等操作的即时反馈一致。

- JobList.vue：onDelete 移除 confirm()，直接 emit('delete')
- i18n（zh-CN/en）：移除已无引用的 deleteConfirm/deleted/deleteFailed 文案

src/i18n/locales/en.js

@@ -32,10 +32,7 @@ export default {
     statusConverting: 'Converting',
     statusPending: 'Queued',
     download: 'Download',
-    delete: 'Delete',
-    deleteConfirm: 'Delete "{name}"?\nIt will no longer be shown to you (admin can still see it; only admin hard-delete truly removes it).',
-    deleted: 'Deleted',
-    deleteFailed: 'Delete failed: {msg}'
+    delete: 'Delete'
   },
   refresh: 'Refresh'
 }

src/i18n/locales/zh-CN.js

@@ -31,10 +31,7 @@ export default {
     statusConverting: '转换中',
     statusPending: '排队中',
     download: '下载',
-    delete: '删除',
-    deleteConfirm: '确定删除「{name}」？\n删除后将不再显示（管理员仍可见，需管理员彻底删除才会清除）。',
-    deleted: '已删除',
-    deleteFailed: '删除失败：{msg}'
+    delete: '删除'
   },
   refresh: '刷新'
 }