feat: add danmuku plugin and i18n setup documentation

- Created a new documentation file for the danmuku plugin with code examples.
- Added a new documentation file for language settings (i18n) with detailed instructions on language imports, default languages, and how to add or modify languages.
- Included code snippets for initializing the Artplayer with different language settings.

CHANGELOG.md

@@ -6,6 +6,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 ## [Unreleased]
 
+## [5.4.0] - 2026-03-12
+
 - Refactor `Parcel` to `Vite`
 - Change `Artplayer.FULLSCREEN_WEB_IN_BODY` defaults to `true`
 - The `reset` method is used to reset video request