feat: add danmuku plugin documentation and i18n setup guide

- Created a new documentation file for the danmuku plugin with code examples.
- Added a comprehensive guide for language settings (i18n) including default languages, importing languages, adding new languages, and modifying existing languages.
- Included code snippets for initializing the Artplayer with different language settings.

feat: implement safe area insets for improved video rotation handling

feat: add console log for safe area insets in autoOrientation plugin

feat: enhance mobile meta tags for better web app support

docs/assets/ts/artplayer.d.ts

@@ -32,6 +32,7 @@ export interface Utils {
   tooltip: (target: HTMLElement, msg: string, pos?: string) => void
   isInViewport: (target: HTMLElement, offset?: number) => boolean
   includeFromEvent: (event: Event, target: HTMLElement) => boolean
+  getSafeAreaInsets: () => { top: number, right: number, bottom: number, left: number }
 
   srtToVtt: (srtText: string) => string
   vttToBlob: (vttText: string) => string