修复：CI 部署环境与 ref 错配、迁移碎片化、图片意图 source_span、章节物化脏版式、会话历史与本地语音不一致

新增：TTS 上传 COS 与分片、章节 reading_segments 物化与快照、markdown 清洗、会话消息 repository、语音 store 重构与相关测试

api/app/core/redis.py

@@ -85,6 +85,7 @@ class RedisService:
         message_type: str = "text",
         voice_session_id: str | None = None,
         timestamp: str | int | None = None,
+        audio_duration_seconds: int | None = None,
     ) -> bool:
         try:
             client = await self.get_client()
@@ -98,6 +99,12 @@ class RedisService:
             }
             if voice_session_id:
                 item["voiceSessionId"] = voice_session_id
+            if (
+                audio_duration_seconds is not None
+                and audio_duration_seconds > 0
+                and message_type == "audio"
+            ):
+                item["durationSeconds"] = int(audio_duration_seconds)
             history.append(item)
             await client.setex(
                 key, self.session_ttl, json.dumps(history, ensure_ascii=False)
@@ -107,6 +114,41 @@ class RedisService:
             logger.error("添加消息失败: %s", e)
             return False
 
+    async def append_tts_audio_url_to_last_ai_message(
+        self, conversation_id: str, url: str
+    ) -> bool:
+        """向最近一条 AI 消息的 ttsAudioUrls 追加 COS 公开 URL。"""
+        if not url:
+            return False
+        try:
+            client = await self.get_client()
+            key = self._conversation_key(conversation_id)
+            history = await self.get_conversation_history(conversation_id)
+            for i in range(len(history) - 1, -1, -1):
+                if history[i].get("role") == "ai":
+                    existing = history[i].get("ttsAudioUrls")
+                    urls: List[str] = (
+                        [x for x in existing if isinstance(x, str)]
+                        if isinstance(existing, list)
+                        else []
+                    )
+                    urls.append(url)
+                    history[i]["ttsAudioUrls"] = urls
+                    break
+            else:
+                logger.warning(
+                    "append_tts_audio_url: no ai message in history conversation_id=%s",
+                    conversation_id,
+                )
+                return False
+            await client.setex(
+                key, self.session_ttl, json.dumps(history, ensure_ascii=False)
+            )
+            return True
+        except Exception as e:
+            logger.error("append_tts_audio_url 失败: %s", e)
+            return False
+
     async def clear_conversation_history(self, conversation_id: str) -> bool:
         try:
             client = await self.get_client()