Stream POC

[ewilliams-cloudera]

POC demonstrating using streaming responses against a direct llm call. Additional work will be necessary to get this fully fleshed out to use. Next steps include:

1. the Python side should kick off evals, question rewrites, etc after the streamed response is finished
2. The simple Python endpoint bypasses functionality for using the data source, which will need to be added
3. The UI will need to use the mutation
4. Will need to add support for query config
5. Will need to replace the current loading chat UI with the streamed response
6. Once the streamed response is done, the UI will need to request the full payload.