GitLab

- Add home_content setting for custom homepage (HTML or iframe URL)
- Inject public settings into index.html to eliminate page flash
- Support ETag caching with automatic invalidation on settings update
- Add Vite plugin for dev mode settings injection
- Refactor HomeView to use appStore instead of local API calls

使用 router.isReady() 等待路由器完成初始导航后再挂载应用，
避免 RouterView 在路由未就绪时渲染空的 Comment 节点。