Phrase mode: count-in no-scoring fix, re-arm timeout for repeated notes, browser QA scripts

scripts/README.md

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+# Browser QA scripts
+
+Synthetic-microphone end-to-end checks for Phrase Mode (puppeteer-core +
+system Chrome). They stub `getUserMedia` with a tunable oscillator feeding a
+`MediaStreamDestination`, so note detection is exercised through the real
+detection pipeline — not only through virtual taps.
+
+Run:
+
+```sh
+npm i --no-save puppeteer-core   # does not modify package.json
+npm run build
+npx vite preview --port 4199 &    # serve dist
+node scripts/phrase_e2e.cjs       # matcher basics (first-note match)
+node scripts/phrase_e2e2.cjs      # repeated notes, release re-attack,
+                                  # timeout re-arm, tempo count-in/misses
+```
+
+In-app debug state is available with `localStorage.phraseDebug = '1'`
+(`window.__phraseDebug()` returns phase, cursor, statuses, summary, pool,
+frame count, mic-gate state). Only ever a QA aid, not part of the UI.