support more optioin about usage in stream mode

[yichuan520030910320]

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Motivation

Fix #954

Modification

adapter and protocol in openai

Checklist

1. Ensure pre-commit pre-commit run --all-files or other linting tools are used to fix potential lint issues.
2. Confirm that modifications are covered by complete unit tests. If not, please add more unit tests for correctness.
3. Modify documentation as needed, such as docstrings or example tutorials.

[Ying1123]

What is wrong with the default mem_fraction_static?

[meetzuber]

I hope all finish reasons are considered as per openai api format.
Please refer below link for more details.
https://platform.openai.com/docs/guides/chat-completions/response-format

---

Every response will include a finish_reason. The possible values for finish_reason are:
stop: API returned complete message, or a message terminated by one of the stop sequences provided via the stop parameter
length: Incomplete model output due to max_tokens parameter or token limit
function_call: The model decided to call a function
content_filter: Omitted content due to a flag from our content filters
null: API response still in progress or incomplete
Depending on input parameters, the model response may include different information.

[yichuan520030910320]

@meetzuber please stay tuned for the function_call and content filter, we will support that in the future

[merrymercy]

please resolve the conflicts and we can merge this