fork(fix): Clone AMLL 并修复 BUG

- 将AMLL Clone到本以地进行修复和优化(emm虽然这很不优雅但是暂时无时间做子模块和Fork)
- 修复在当前播放歌词行不可见的视口Seek会出现滚动偏移的问题

amll-local/packages/docs/scripts/copy-playground.js

@@ -0,0 +1,5 @@
+import fs from "node:fs";
+
+fs.rmSync("dist/playground", { recursive: true, force: true });
+fs.cpSync("../playground/core/dist", "dist/playground", { recursive: true });
+console.log("Playground copied to dist/playground");