Refactor chat stream handling to use BotChatSession

- Updated imports and references from ChatStream to BotChatSession across multiple files.
- Adjusted method signatures and internal logic to accommodate the new session management.
- Ensured compatibility with existing functionality while improving code clarity and maintainability.

src/chat/replyer/replyer_manager.py

@@ -1,7 +1,7 @@
 from typing import Dict, Optional
 
 from src.common.logger import get_logger
-from src.chat.message_receive.chat_stream import ChatStream, get_chat_manager
+from src.chat.message_receive.chat_manager import BotChatSession, chat_manager as _chat_manager
 from src.chat.replyer.group_generator import DefaultReplyer
 from src.chat.replyer.private_generator import PrivateReplyer
 
@@ -14,7 +14,7 @@ class ReplyerManager:
 
     def get_replyer(
         self,
-        chat_stream: Optional[ChatStream] = None,
+        chat_stream: Optional[BotChatSession] = None,
         chat_id: Optional[str] = None,
         request_type: str = "replyer",
     ) -> Optional[DefaultReplyer | PrivateReplyer]:
@@ -24,7 +24,7 @@ class ReplyerManager:
         model_configs 仅在首次为某个 chat_id/stream_id 创建实例时有效。
         后续调用将返回已缓存的实例，忽略 model_configs 参数。
         """
-        stream_id = chat_stream.stream_id if chat_stream else chat_id
+        stream_id = chat_stream.session_id if chat_stream else chat_id
         if not stream_id:
             logger.warning("[ReplyerManager] 缺少 stream_id，无法获取回复器。")
             return None
@@ -39,15 +39,14 @@ class ReplyerManager:
 
         target_stream = chat_stream
         if not target_stream:
-            if chat_manager := get_chat_manager():
-                target_stream = chat_manager.get_stream(stream_id)
+            target_stream = _chat_manager.get_session_by_session_id(stream_id)
 
         if not target_stream:
             logger.warning(f"[ReplyerManager] 未找到 stream_id='{stream_id}' 的聊天流，无法创建回复器。")
             return None
 
         # model_configs 只在此时（初始化时）生效
-        if target_stream.group_info:
+        if target_stream.is_group_session:
             replyer = DefaultReplyer(
                 chat_stream=target_stream,
                 request_type=request_type,