[Feature Request] Add custom headers option to the settings

[PROPHESSOR]

It's useful when you want to use ChatGPT for example or if your API uses some kind of authorization

[Asherathe]

Yes, even people using an LLM locally may have access secured with an API key to prevent random web pages from spying on their text generation.

[kbradsha]

I see information in the documentation referencing an API key in the localwriter.json but it never seems to work.
All I get is 401 Unauthorized when attempting to use it. I know the API key I'm using is correct. It's only 3 characters long.