Separate ControlNet / VAE / Lora / Diffusion model loading.

[LSXAxeller]

In the current implementation (leejet/stable-diffusion.cpp@4a6e36e/stable-diffusion.h#L121), models like ControlNet, VAE, Lora, Embeddings, and Tiny AutoEncoder (Taesd) can only be loaded alongside the Stable Diffusion model. This means that switching between different ControlNet models (e.g., Canny, Depth, OpenPose) or other model types requires completely reloading the Stable Diffusion model, which is inefficient, disruptive and time consuming.

Is there a way to allows these models to be loaded independently from the Stable Diffusion model? This would enable users to quickly swap between different model configurations without restarting the entire Stable Diffusion process, significantly improving workflow flexibility