Add OpenAI endpoint variable so can set custom endpoint

[meb427]

OpenAI API's are now golden standard for multiple providers.

Lately even GCP/Google announced support for the API format.

Currently we can only add an OpenAI key.
I would like to be able to override that with OpenAI endpoint as that would allow me more choice of backend AI's and that way users can pick a lot more choices. Even Grok have OpenAI endpoint : https://api.groq.com/openai/v1
https://console.groq.com/docs/openai

Even Ollama already have that endpoint support.

[ItzCrazyKns]

Custom OpenAI provider can be used from the settings menu in the UI.

[meb427]

I want to use that as variable when starting docker.