📝 docs(prd): update task status and story completion

- mark "文档适当更新" task as completed in epic-004
- update story 004.001 status from "Ready for Done" to "Done"

docs/prd/epic-004-api-actual-request-testing.md

@@ -62,7 +62,7 @@
 - [✅] Story 004.001完成且验收标准满足
 - [✅] 用户API功能通过实际请求测试验证
 - [✅] 集成点正常工作
-- [ ] 文档适当更新（进行中）
+- [✅] 文档适当更新（已完成）
 - [✅] 现有功能无回归
 
 ## 验证检查清单

docs/stories/004.001.story.md

@@ -4,7 +4,7 @@
 docs/prd/epic-004-api-actual-request-testing.md
 
 ## Status
-Ready for Done
+Done
 
 ## Story
 **As a** 质量保证工程师