✨ feat(spot-strategy): 新增抢占式实例注解支持

- 添加故事 1.1 的实现工件文档，定义抢占式实例开关注解功能
- 更新 sprint 状态文件，将故事标记为 ready-for-dev 并开始 epic-1 的开发

docs/sprint-status.yaml

@@ -5,15 +5,10 @@ generated: "2025-11-26"
 project: "vk-eci"
 sprint: "Sprint-1"
 
-stories:
-  - id: "STORY-001"
-    title: "实现 ECI 抢占式实例 SpotToBeReleased 事件处理"
-    file: "docs/stories/spot-instance-event-handling.md"
-    status: "TODO"
-    priority: "高"
-    effort: "中等"
-    assignee: ""
-    created: "2025-11-26"
+# BMAD 故事状态跟踪
+development_status:
+  "1-1-spot-strategy-annotation": "ready-for-dev"
+  "epic-1": "in-progress"
 
 # 故事状态定义
 # TODO - 待开始