--- fixes: - | Fixed issue with MistralChatGenerator not returning a `finish_reason` when using streaming. Fixed by adjusting how we look for the `finish_reason` when processing streaming chunks. Now, the last non-None `finish_reason` is used to handle differences between OpenAI and Mistral. enhancements: - | - Refactored the processing of streaming chunks from OpenAI to simplify logic. - Added tests to ensure expected behavior when handling streaming chunks when using include_usage=True.