langchain

22e6d909 - langchain_mistralai: Include `finish_reason` in response metadata when parsing MistralAI chunks to`AIMessageChunk` (#31667)

langchain_mistralai: Include `finish_reason` in response metadata when parsing MistralAI chunks to`AIMessageChunk` (#31667) ## Description <!-- What does this pull request accomplish? --> - When parsing MistralAI chunk dicts to Langchain to `AIMessageChunk` schemas via the `_convert_chunk_to_message_chunk` utility function, the `finish_reason` was not being included in `response_metadata` as it is for other providers. - This PR adds a one-liner fix to include the finish reason. - fixes: https://github.com/langchain-ai/langchain/issues/31666