Choosing quant by tensor pattern with the help of regex like llama.cpp

[Greatz08]

FWIW, I've been working on an option for sd.cpp to choose the quant by tensor pattern, a la llama.cpp's overridetensors: e128cfa . The conversion itself already works; could be useful for testing.

@wbruna This was your message on #696 issue, so i wanted to know if you were able to finish your work on this feature. I recently experienced the power of using --override-tensor in llama.cpp which helped me load bigger model easily and i was able to improve performance of inference, so i was interested to see if it was possible for image generation models like flux, so i searched for it and got to know about this another great project.

I tried to find info regarding similar feature in this project but was not able to find it and then i tried to search in this project issue and got to know that someone was working on it, so was just interested to know if you were able achieve similar thing like llama.cpp with --override-tensor in this project :-))

[wbruna]

The convert functionality is already working. It's still missing weight quantization on model loading, but I guess the file conversion would be more useful anyway. I'll send a PR later today.