Add Negative Prompts support

[chavinlo]

I have seen many webUIs have it, but as far as I know no bot, or frontend has implemented it yet. The closest thing I could find is: https://github.com/invoke-ai/InvokeAI/search?q=negative

[parlance-zz]

I haven't personally investigated this so I can't promise any kind of timeframe for it, but I will add it to the list and plan to include it.

Thank you.

[keturn]

It might get included upstream, there's an open PR for it: huggingface/diffusers#549

[parlance-zz]

It might get included upstream, there's an open PR for it: huggingface/diffusers#549

Thanks for the heads up, will hold off for now.

[parlance-zz]

The integration of haffried's GRPC server means we get this mostly for free now, I will move it up the list as I do not need to change much to support it now.

[aaronsantiago]

+1 to negative prompt support

[parlance-zz]

[parlance-zz]

This is coming next, along with arbitrary weighting syntax.

[parlance-zz]

negative prompts are in, weight syntax is next but will be a separate issue