pixijs 是做什么的？
Use this skill when loading and managing resources in PixiJS v8. Covers Assets.init, Assets.load/add/unload, bundles, manifests, background loading, onProgress, caching, spritesheets, video textures, web fonts, bitmap fonts, animated GIFs, compressed textures, SVG as texture or Graphics, resolution detection, per-asset data options, and forcing a specific loader with the parser field (for extension-less URLs). Triggers on: Assets, Assets.load, Assets.init, loadBundle, manifest, backgroundLoad, S