fix(vue): support reactive lyric lines

[sin6626]

Summary

• unwrap Vue reactive proxies before passing lyricLines to Core
• add a regression test covering deeply reactive ref<LyricLine[]>() data
• use a regular ref in the Vue playground and document the supported usage in English and Chinese

Problem

The Vue binding currently forwards a deeply reactive lyrics array directly to Core. Core clones lyric lines with structuredClone, which throws a DataCloneError when the value is a Vue Proxy. As a result, using the natural Vue API (ref([])) can leave the lyric player empty.

Verification

• pnpm --filter @applemusic-like-lyrics/vue test
• pnpm --filter @applemusic-like-lyrics/vue typecheck
• pnpm test:libs
• pnpm release:plan:check
• Vue package build
• Biome lint on changed Vue source and test files