fix(conversation): 修复实时会话 TTS/回复被离屏 WS 抢占

- 列表预热仅预取消息缓存，避免后台 WebSocket 覆盖服务端连接
- RealtimeSession UI 回调按 owner 独占，防止 offscreen 覆盖聊天页
- 列表页聚焦时再 prewarm，会话页 TTS 入队优先 base64
- 管线下发 TTS 同时带 audio_base64 与 audio_url；协议说明同步
- 移除 TTS 排查用前后端调试日志，保留错误/告警
- 补充 WS / RealtimeSession / entry-warmup / 播放器相关单测

Co-authored-by: Cursor <cursoragent@cursor.com>

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

@@ -289,13 +289,6 @@ async def websocket_endpoint(
                         data = message.get("data") or {}
                         text_message = data.get("text", "")
                         tts_this_turn = bool(data.get("tts_this_turn"))
-                        # 长期保留：TTS 决策入口可见性（INFO 级别即可定位 FE 是否带 tts_this_turn）
-                        logger.info(
-                            "ws.user_message tts_this_turn={} conversation_id={} text_len={}",
-                            tts_this_turn,
-                            conversation_id,
-                            len(text_message or ""),
-                        )
 
                         if text_message:
                             can_send, quota_msg = await check_ws_quota(
@@ -397,16 +390,6 @@ async def websocket_endpoint(
                         is_last = bool(data.get("is_last", False))
                         audio_duration = int(data.get("duration", 0) or 0)
                         tts_this_turn_segment = bool(data.get("tts_this_turn"))
-                        # 长期保留：分段语音轮的 TTS 决策入口可见性
-                        logger.info(
-                            "ws.audio_segment tts_this_turn={} is_last={} "
-                            "conversation_id={} voice_session_id={} segment_index_raw={}",
-                            tts_this_turn_segment,
-                            is_last,
-                            conversation_id,
-                            voice_session_id,
-                            segment_index_raw,
-                        )
 
                         if not audio_base64:
                             await manager.send_message(
@@ -524,13 +507,6 @@ async def websocket_endpoint(
                         audio_base64 = data.get("audio_base64", "")
                         audio_duration = data.get("duration", 0)
                         tts_this_turn = bool(data.get("tts_this_turn"))
-                        # 长期保留：单次整段音频路径的 TTS 决策入口可见性
-                        logger.info(
-                            "ws.audio_message tts_this_turn={} conversation_id={} duration_s={}",
-                            tts_this_turn,
-                            conversation_id,
-                            audio_duration,
-                        )
 
                         if audio_base64:
                             can_send, quota_msg = await check_ws_quota(
@@ -719,15 +695,6 @@ async def websocket_endpoint(
                             st_val = None
                         else:
                             st_val = str(st).strip() or None
-                        logger.info(
-                            "ws.TTS_REQUEST received conversation_id={} user_id={} "
-                            "assistant_message_id={} segment_index={} segment_text_len={}",
-                            conversation_id,
-                            user_id,
-                            str(aid).strip(),
-                            seg_idx,
-                            len(st_val or ""),
-                        )
                         ok, err_msg = await handle_tts_request_on_demand(
                             conversation_id=conversation_id,
                             user_id=user_id,
@@ -736,15 +703,6 @@ async def websocket_endpoint(
                             segment_text=st_val,
                             db=db,
                         )
-                        logger.info(
-                            "ws.TTS_REQUEST handled conversation_id={} assistant_message_id={} "
-                            "segment_index={} ok={} err_msg={}",
-                            conversation_id,
-                            str(aid).strip(),
-                            seg_idx,
-                            ok,
-                            err_msg,
-                        )
                         if not ok:
                             await manager.send_message(
                                 conversation_id,