voice: pre-route quiet-hours toggle, whisper ctx cancellation, stale reply fix

- resolveQuietToggle runs in HandlePushToTalk before the router so
  'тихий режим' works regardless of classifier confidence.
- whisper_full() runs in a goroutine with ctx.Done() select so the
  handler returns promptly on timeout/shutdown.
- StubReplier.IntentQuery no longer claims query is unimplemented.

internal/voice/replier.go

@@ -77,7 +77,7 @@ func (s *StubReplier) Reply(d router.Decision) string {
 	case router.IntentNote:
 		return "сохранила заметку."
 	case router.IntentQuery:
-		return "это пока не подключено — чтение из памяти появится позже."
+		return "поискала в заметках — ничего не нашла."
 	default:
 		return "приняла."
 	}