The function calling needs improvement

[Yimi81]

Due to the fact that function calls call API twice, and the first call returns results that I do not want to display on the dialogue UI interface, this is difficult to achieve. The reason is that

1. The current conversation history is directly recorded based on ChatItems
2. HandleSendMessageButton method always immediately adds the SHttpGPTChatItem to ChatBox, and I hope to hide the response of the first invocation of the functional_call .
   May I ask if you have any suggestions for me? What I hope is that when players have normal conversations, the API's return results can be directly displayed, but when a function call is triggered, the first return result is hidden and only the final one is returned

[Yimi81]