feat(conversation): TTS 投递与 WebSocket 管线；客户端播放门禁与会话页联动；COS 键与迁移脚本调整

api/app/features/conversation/ws/router.py

@@ -26,6 +26,7 @@ from app.features.conversation.ws.pipeline import (
     _mark_conversation_active,
     _voice_session_id_from_client_segment_id,
     background_runner,
+    bump_tts_cancel_epoch,
     chat_orchestrator,
     cleanup_segment_states,
     get_or_create_segment_state,
@@ -604,6 +605,9 @@ async def websocket_endpoint(
                                 },
                             )
 
+                    elif msg_type == MessageType.TTS_CANCEL:
+                        bump_tts_cancel_epoch(conversation_id)
+
                     elif msg_type == MessageType.END_CONVERSATION:
                         conversation.status = "ended"
                         conversation.ended_at = datetime.now(timezone.utc)