Update the streaming implementation, which currently uses Lanarky for Langchain streaming, to adhere to the `EventSource` protocol, specifically referencing changes after v0.8.
### ⚠️ Please check that this feature request hasn't been suggested before. - [X] I searched previous [Ideas in Discussions](https://github.com/reworkd/AgentGPT/discussions/categories/ideas) didn't find any similar feature requests. - [X] I searched previous [Issues](https://github.com/reworkd/AgentGPT/labels/enhancement) didn't find any similar feature requests. ### 🔖 Feature description The project uses lanarky for langchain streaming. After v0.8, - [`EventSource`](https://developer.mozilla.org/en-US/docs/Web/API/EventSource) protocol is enforced for server-sent events - `StreamingResponse` for langchain objects has been refactored Related documentation: https://lanarky.ajndkr.com/learn/adapters/langchain/fastapi/#streaming ### ✔️ Solution As the author of lanarky, I would love to assist here. I can handle the python side but someone else needs to take over the client side changes. ### ❓ Alternatives _No response_ ### 📝 Additional Context _No r