feat(inbounds): add multi-select and bulk delete

Mirror the clients page: checkbox selection on the desktop table and on
mobile cards, with a danger Delete button in the toolbar that removes all
selected inbounds in one call.

Backend adds POST /panel/api/inbounds/bulkDel, which loops the existing
DelInbound per id (xray restarts at most once) and returns {deleted,
skipped}. Frontend shows a confirm modal plus a result toast, clears the
selection on success, adds bulk-delete i18n keys across all 13 languages,
and documents the endpoint in the in-panel API docs.

web/translation/zh-CN.json

@@ -296,6 +296,10 @@
       "deleteConfirmContent": "将删除此入站及其所有客户端。该操作不可撤销。",
       "resetConfirmTitle": "重置 \"{remark}\" 的流量？",
       "resetConfirmContent": "将此入站的上/下行计数器清零。",
+      "selectedCount": "已选 {count} 项",
+      "selectAll": "全选",
+      "bulkDeleteConfirmTitle": "删除 {count} 个入站？",
+      "bulkDeleteConfirmContent": "将删除所选入站及其所有客户端。该操作不可撤销。",
       "cloneConfirmTitle": "克隆入站 \"{remark}\"？",
       "cloneConfirmContent": "使用新端口和空客户端列表创建副本。",
       "delAllClients": "删除所有客户端",
@@ -421,6 +425,8 @@
         "inboundsUpdateSuccess": "入站连接已成功更新",
         "inboundUpdateSuccess": "入站连接已成功更新",
         "inboundCreateSuccess": "入站连接已成功创建",
+        "bulkDeleted": "已删除 {count} 个入站",
+        "bulkDeletedMixed": "已删除 {ok} 个，失败 {failed} 个",
         "inboundDeleteSuccess": "入站连接已成功删除",
         "inboundClientAddSuccess": "已添加入站客户端",
         "inboundClientDeleteSuccess": "入站客户端已删除",