release: bump version to 0.27.8

docs/version-history.md

@@ -16,12 +16,13 @@
 ## Current Version
 
 - `main` 当前主线历史推导到：`0.16.5`
-- `dev` 当前开发分支历史推导到：`0.27.7`
+- `dev` 当前开发分支历史推导到：`0.27.8`
 
 ## Timeline
 
 | Version | Type | Branch | Commit | Summary |
 | --- | --- | --- | --- | --- |
+| `0.27.8` | bugfix | `dev` | `pending` | 统一 Earth HUD 默认折叠逻辑，修复图例与图层面板箭头和底边阈值行为 |
 | `0.27.7` | bugfix | `dev` | `pending` | 修复电视直播源编辑持久化问题，清理表格空白占位列并统一可折叠操作列 |
 | `0.27.6` | improvement | `dev` | `pending` | BGP/用户表格滚动条修复，Playground 响应式按钮与输入框收起优化 |
 | `0.27.5` | bugfix | `dev` | `pending` | 统一控制台自定义滚动条，修复 alerts/BGP 响应式滚动与采集进度完成态显示 |