fix: send WhatsApp audio via native bridge media path

gateway/platforms/whatsapp.py

@@ -704,6 +704,23 @@ async def send_document(
             file_name or os.path.basename(file_path),
         )
 
+    async def send_voice(
+        self,
+        chat_id: str,
+        audio_path: str,
+        caption: Optional[str] = None,
+        reply_to: Optional[str] = None,
+        metadata: Optional[Dict[str, Any]] = None,
+        **kwargs,
+    ) -> SendResult:
+        """Send an audio file natively via the WhatsApp bridge.
+
+        OGG/Opus files are treated by the Node bridge as PTT voice notes
+        (ptt=true); MP3/WAV/M4A are sent as normal audio attachments.
+        """
+        del reply_to, metadata, kwargs
+        return await self._send_media_to_bridge(chat_id, audio_path, "audio", caption)
+
     async def send_typing(self, chat_id: str, metadata=None) -> None:
         """Send typing indicator via bridge."""
         if not self._running or not self._http_session:

tests/gateway/test_whatsapp_connect.py

@@ -211,6 +211,24 @@ async def test_closed_when_bridge_dies_phase1(self):
         assert adapter._bridge_log_fh is None
 
 
+class TestSendVoice:
+    """Regression tests for native WhatsApp audio sending."""
+
+    @pytest.mark.asyncio
+    async def test_send_voice_routes_to_bridge_audio_media(self):
+        adapter = _make_adapter()
+        adapter._send_media_to_bridge = AsyncMock(
+            return_value=MagicMock(success=True, message_id="wa-audio-1")
+        )
+
+        result = await adapter.send_voice("chat-123", "/tmp/voice.ogg", caption="hello")
+
+        assert result.success is True
+        adapter._send_media_to_bridge.assert_awaited_once_with(
+            "chat-123", "/tmp/voice.ogg", "audio", "hello"
+        )
+
+
 class TestBridgeRuntimeFailure:
     """Verify runtime bridge death is surfaced as a fatal adapter error."""