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/features/conversation/service.py

@@ -6,7 +6,11 @@ from datetime import datetime, timezone
 from fastapi import HTTPException
 from sqlalchemy.ext.asyncio import AsyncSession
 
-from app.core.cos_url_keys import extract_cos_object_key_if_owned
+from app.core.cos_url_keys import (
+    collect_cos_keys_from_conversation_history,
+    collect_cos_keys_from_tts_url_list,
+    extract_cos_object_key_if_owned,
+)
 from app.core.logging import get_logger
 from app.core.redis import redis_service
 from app.core.storage_purge import delete_object_storage_keys_best_effort
@@ -67,16 +71,24 @@ def _build_messages_from_history(
             if voice_session_id in seen_audio_sessions:
                 continue
             seen_audio_sessions.add(voice_session_id)
-        messages.append(
-            {
-                "id": f"{conversation_id}_msg_{idx}",
-                "conversationId": conversation_id,
-                "content": msg.get("content", ""),
-                "senderType": "user" if role == "human" else "assistant",
-                "timestamp": _message_timestamp_ms(msg, fallback_timestamp),
-                "messageType": message_type,
-            }
-        )
+        item: dict = {
+            "id": f"{conversation_id}_msg_{idx}",
+            "conversationId": conversation_id,
+            "content": msg.get("content", ""),
+            "senderType": "user" if role == "human" else "assistant",
+            "timestamp": _message_timestamp_ms(msg, fallback_timestamp),
+            "messageType": message_type,
+        }
+        if voice_session_id and role == "human":
+            item["voiceSessionId"] = voice_session_id
+        ds = msg.get("durationSeconds")
+        if isinstance(ds, (int, float)) and ds > 0:
+            item["durationSeconds"] = int(ds)
+        if role == "ai":
+            tts = msg.get("ttsAudioUrls")
+            if isinstance(tts, list) and tts:
+                item["ttsAudioUrls"] = [x for x in tts if isinstance(x, str)]
+        messages.append(item)
     return messages
 
 
@@ -202,11 +214,21 @@ class ConversationService:
                 self._db, conversation_id
             )
         )
+        try:
+            hist = await redis_service.get_conversation_history(conversation_id)
+            cos_keys |= collect_cos_keys_from_conversation_history(hist)
+        except Exception:
+            pass
         segments = await repo.get_segments_for_conversation(conversation_id, self._db)
         for seg in segments:
             k = extract_cos_object_key_if_owned(seg.audio_url)
             if k:
                 cos_keys.add(k)
+            raw_tts = getattr(seg, "tts_audio_urls", None)
+            if isinstance(raw_tts, list):
+                cos_keys |= collect_cos_keys_from_tts_url_list(
+                    [str(x) for x in raw_tts if isinstance(x, str)]
+                )
 
         await self._clear_history(conversation_id)
         conv.deleted_at = datetime.now(timezone.utc)