chore(backlog): 记录 g143 完成

.ua/backlog.json

@@ -1507,7 +1507,7 @@
       "motivation": "「新建 / 设置」这类页签级操作只能塞进页签数组或浮在页签栏外，垂直不对齐、分隔线断掉；调用方还得自己包一层 flex",
       "acceptance": "tabs 新增 extra：与页签同一行、共用一条分隔线，不传时 DOM 结构不变（纯增量）；文档 props/steps 与演示同步；npm run check 全绿",
       "notes": "自补：既有组件可用性细节",
-      "status": "open"
+      "status": "done"
     }
   ]
 }

.ua/iterations.log

@@ -187,3 +187,4 @@
 {"ts":"2026-10-26T15:35:04+08:00","id":"g140","result":"done","commit":"e40cd2c","summary":"dataTable 新增 onRowClick：传了行变 tabindex=0 并响应点击/Enter/空格，未传保持纯展示；文件压到 199 行"}
 {"ts":"2026-10-26T15:36:29+08:00","id":"g141","result":"done","commit":"6cde618","summary":"notification 新增 placement 四角停靠：每角独立容器与 3 条上限，顶部角落 column-reverse 让新通知贴边出现"}
 {"ts":"2026-10-26T15:37:34+08:00","id":"g142","result":"done","commit":"5af2139","summary":"space 新增 split：只在 2 个以上子元素间插分隔符，aria-hidden + 弱化色 + 不可选中"}
+{"ts":"2026-10-26T15:38:51+08:00","id":"g143","result":"done","commit":"3058da1","summary":"tabs 新增 extra 右侧操作区：与页签同一行共用分隔线，不传时 DOM 结构不变"}