chore(changelog): 领取 5338 管理后台任务

修改原因：#5338 的按订单分窗尚未对 merged rows 应用 route 状态最终过滤。

修改内容：将 changelog 迁移为 claimed，记录 frontend_owner=hl-ui-pi。

实际验证：source 46 项测试和 git diff --check 通过。

changelogs-v2/2026-07/28_5338_Fleet按订单分窗状态集合守恒-修改接口-管理后台.md

@@ -6,13 +6,13 @@ consumer: "admin"
 change_type: "修改接口"
 backend_status: "deployed"
 gateway_status: "not_required"
-frontend_status: "pending"
-frontend_owner: ""
+frontend_status: "claimed"
+frontend_owner: "hl-ui-pi"
 frontend_ref: ""
 target_release: ""
 verified_at: ""
 status_note: "frontend-only：复用 #4760 grid/unassigned 与 #5301 coarse status 已部署契约，无新增后端发布；本次只交接前端最终集合过滤，fresh gateway probe 不适用"
-updated_at: "2026-07-28"
+updated_at: "2026-07-29"
 base: "dev-v3"
 ---