Adding Support for Qwen3.5

[johnmai-dev]

Port of huggingface/transformers#43830

TODO:

• Test Qwen3.5 Model https://huggingface.co/Qwen/Qwen3.5-9B-Instruct

[johnmai-dev]

I noticed that @JJJYmmm 大佬 is submitting PRs to multiple LLM inference repositories to add support for Qwen3.5. Could you help review these PRs?❤️❤️

Since Qwen3.5 has not been officially released yet, I can currently only proceed with the porting work based on huggingface/transformers#43830, but I’m unable to complete full testing and validation at this stage.

[JJJYmmm]

sure, i would test this branch tonight.

[johnmai-dev]

sure, i would test this branch tonight.

Thank you very much 🍻

[JJJYmmm]

Hi, I noticed that your branch is based on an older version and has some conflicts with transformers v5. I've therefore ported my vlm implementation from Blaizzy/mlx-vlm#722 to this repo and verified it with actual checkpoint loading.

Since this PR would require too many changes, I've opened a fresh one and added you as a co-author. Thanks again!

[johnmai-dev]

New PR -> #869