fix: harden image handling and update docs

core/repository.py

@@ -18,7 +18,16 @@ class DataRepository:
 
     # --- 聊天记录 (异步化) ---
 
-    async def save_chat(self, platform: str, user_id: str, content: str, direction: str, acc_id: str = "", image_urls: list = None):
+    async def save_chat(
+        self,
+        platform: str,
+        user_id: str,
+        content: str,
+        direction: str,
+        acc_id: str = "",
+        image_urls: list = None,
+        msg_type: int = 0,
+    ):
         """异步持久化存储聊天记录"""
         # 将图片URL列表转为\n分隔的字符串
         urls_str = "\n".join(image_urls) if image_urls else ""
@@ -29,6 +38,7 @@ class DataRepository:
             direction=direction,
             platform=platform,
             acc_id=acc_id,
+            msg_type=msg_type,
             image_urls=urls_str
         )
 
@@ -42,6 +52,8 @@ class DataRepository:
                 {
                     "role": role,
                     "content": r["message"],
+                    "msg_type": r.get("msg_type", 0),
+                    "image_urls": r.get("image_urls", ""),
                     "timestamp": r.get("timestamp", ""),
                 }
             )