PR2: naratiune vocala (SpeechSynthesis, D10) - opt-in din builder

Feature nou (vocea nu exista deloc). Opt-in via checkbox 'voice' in builder
(off implicit), buton toggle in bara chrome a campaniei (parintele detine).
Voicing orchestrator-only, uniform pe toate 5 motoarele (fara dublu-citit):
povestea la 'Incepe aventura', intrebarea camerei la roomReady, mesajul final.

Edge cases (toate tratate):
- getVoices() gol sincron -> re-citire la onvoiceschanged.
- fara voce ro-* -> vocea default a sistemului (doar u.lang='ro-RO').
- speechSynthesis.cancel() in hideAll() -> fara replici fantoma la schimbarea scenei.
- fara 'speechSynthesis' in window -> buton ascuns, totul no-op.
- window.voiceSay expus pe parinte pt. viitor (replici motoare cu guard typeof).

Bug prins de test: #btn-voice{display:inline-flex} batea UA [hidden] ->
adaugat #btn-voice[hidden]{display:none}.

Test nou smoke #9b (voce opt-in: buton, citeste poveste/intrebare, cancel,
toggle) + asertare buton-ascuns cand voice=false. Suita 25/25. Demo regenerat.
AGENTS.md/TODOS actualizate.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

AGENTS.md

@@ -20,9 +20,9 @@ sursa de adevăr tehnică pentru agenți.
 python3 -m http.server 8000
 
 # Teste (Playwright; fără package.json commitat — vezi tests/AGENTS.md):
-npx playwright test tests/smoke.mjs                    # suita completă: 24/24
+npx playwright test tests/smoke.mjs                    # suita completă: 25/25
 npx playwright test tests/smoke.mjs --grep @regresie   # regresie: 14
-npx playwright test tests/smoke.mjs --grep @campanie   # campanie E2E: 10
+npx playwright test tests/smoke.mjs --grep @campanie   # campanie E2E: 11
 ```
 
 ## Durable Rules (repo-wide)