changelog(#5552): 补 frontend_ref 说明（前端字段已存在，仅后端取值变化）

changelogs-v2/2026-08/05_5552_派车板详情日历价列兑底回显-修改接口-管理后台.md

@@ -9,7 +9,7 @@ backend_status: "deployed"
 gateway_status: "verified"
 frontend_status: "implemented"
 frontend_owner: "pi-main-session"
-frontend_ref: ""
+frontend_ref: "N/A：前端字段已存在，仅后端取值变化，无需前端改动"
 target_release: ""
 verified_at: ""
 status_note: ""