支持按 chunk 返回的 HTTP 客户端

This feature is particularly useful for accessing large model services. Later, we will provide an example of a conversation with "DeepSeek". The interface header file is as follows: https://GitHub.com/sogou/workflow/blob/master/src/client/WFHttpChunkedClient.h. "WFHttpChunkedClient" is a static class used to create HTTP tasks based on chunk callbacks, of type "WFHttpChunkedTask". Here is an example: