add abort controller

[floomby]

There should be a way to abort fetch requests. The openai api fairly often does not respond, this leaves the request in limbo.

This is a bit tricky is because with the new way functions are handled passing an abort controlled in as part of the options to sendMessage will not work (no way to reuse abort controllers, and you would need one for each function return). Perhaps just a simple timeout that is cleared if the api responds would be all that is needed.