[Feature]We hope to add new model download sources

I truly appreciate Unsloth Studio and find it a fantastic tool. However, I've noticed that while all Unsloth quantized models are also published on ModelScope, ModelScope is not integrated as a built-in download source within the studio. This omission significantly affects the model downloading experience, and I must admit that the download process has repeatedly deterred me from using the software more frequently. I sincerely hope this could be considered for future updates.