feat(notifier): route TTS to tablet when TABLET_TTS_ENABLED

When TABLET_URL and VOICE_API_KEY are set, the tablet handles TTS
via its ElevenLabs proxy — local speak() is skipped. Controlled
by TABLET_TTS_ENABLED (default true when tablet is configured).

- notifier.speak_locally() — gate used by all local speech paths
- llm._maybe_speak — no-op when tablet plays the voice
- modes._handle_reset — emits response event and skips local speak
  when tablet TTS is on; keeps spoken fallback otherwise

Tablet side in smart-home-tablet repo: /api/voice/tts endpoint +
VoiceOverlay audio playback (commit ba2e… pending).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

satellite/llm.py

@@ -67,7 +67,8 @@ def _post_with_retry(session, url, headers, payload):
 def ask_agent_stream(text: str, agent_id: str = "cosmo") -> str:
     """Отправляет запрос к OpenClaw gateway и озвучивает ответ."""
     def _maybe_speak(t: str):
-        if t.strip():
+        # Если TTS на планшете — пропускаем локальный звук, планшет зачитает по response event.
+        if t.strip() and notifier.speak_locally():
             speak(t, agent_id)
 
     cfg = AGENTS.get(agent_id, AGENTS["cosmo"])