Hudini - Support Hatz AI, or Custom Endpoints

Currently, Hudini can only be configured with OpenAI, Azure OpenAI, or Grok, and the endpoints for these are hardcoded to the respective providers. This means that something like Hatz, though using an OpenAI compatible API key, is unable to work.

It would be great if we could configure a custom endpoint for Hudini AI to be able to set it up with other providers.