Stabilize karaoke and lyrics playback rerenders

[ryokun6]

Summary

• stabilized karaoke playback callback identities so elapsed-time ticks no longer churn menu/control props
• memoized karaoke menu/control trees and expensive menu-bar derived data to reduce avoidable rerenders
• memoized lyrics row rendering so inactive rows stay stable while active timed rows continue smooth highlighting
• moved interlude exit flag transition out of render phase to an effect for deterministic render behavior

Testing

• bun test tests/test-karaoke-interlude-display.test.ts tests/test-furigana-word-spacing.test.ts
• bun run build
• manual karaoke playback check in browser (playback running, lyrics progressing, pause/resume interaction)

Walkthrough artifacts

  

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Last updated at: 2026-04-05 00:46:05 CET