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 configurations.

docs/assets/ts/artplayer-proxy-canvas.d.ts

@@ -6,5 +6,5 @@ declare const artplayerProxyCanvas: (option?: Option) => (art: Artplayer) => Res
 
 export default artplayerProxyCanvas
 
-export = artplayerProxyCanvas;
-export as namespace artplayerProxyCanvas;
+export = artplayerProxyCanvas
+export as namespace artplayerProxyCanvas;