[Feature Request] Support for SDXS-512, allowing for real-time image generation on the CPU (~0.6 seconds per image)

[JohnAlcatraz]

It would be great if support for the SDXS-512 model could be added: https://github.com/IDKiro/sdxs

Especially for quickly generating images on the CPU, this is a major new development, so it would fit this project really well. https://github.com/rupeshs/fastsdcpu already supports it (requires Python though and really isn't lightweight and dependency-free like stable-diffusion.cpp).

I benchmarked SDXS-512 in FastSDCPU on my CPU (3950X):

FastSDCPU Regular: RAM Usage: 700 MB Image Generation Time (Latency): 2 seconds

FastSDCPU OpenVINO: RAM Usage: 3.6 GB Image Generation Time (Latency): 0.6 seconds

So it's really very fast, and even super memory efficient (when not using OpenVINO). And it even looks much better than the best reasonably fast results I can get with stablediffusion.cpp, which is using Dreamshaper LCM with ~5 steps, 2 GB RAM usage and 19 seconds generation time. SDXS-512 looks better, is 20 times faster and uses only 1/3 the RAM - and that's with a Python implementation.