修复interest_value为None的情况，确保在计算兴趣值时不会出现错误。将interest_value的默认值设置为0.0，以提高代码的健壮性。

src/chat/message_receive/message.py

@@ -117,10 +117,7 @@ class MessageRecv(Message):
 
         self.priority_mode = "interest"
         self.priority_info = None
-        self.interest_value: float = None  # type: ignore
-        
-        self.key_words = []
-        self.key_words_lite = []
+        self.interest_value: float = 0.0
 
     def update_chat_stream(self, chat_stream: "ChatStream"):
         self.chat_stream = chat_stream