Generic RAG integration

[kylebuckingham]

Hi there,

I was hoping to enable OpenUI users to select an arbitrary number of RAG providers that anyone using OpenUI could use (similar to how you can already choose different models). The idea is that the end user could select which RAG sources they would want to integrate. These could be local sources or external sources.

I was going to just add a PR, but I thought maybe I'd ask around first. I'd imagine the architecture would look similar to how different models are leveraged currently.

Full disclosure: I work for a company building a RAG data provider.

Any thoughts?