model: support youtu-vl model (#18479)
* Support Youtu-VL Model
* merge code
* fix bug
* revert qwen2 code & support rsplit in minja.hpp
* update warm info
* fix annotation
* u
* revert minja.hpp
* fix
* Do not write routed_scaling_factor to gguf when routed_scaling_factor is None
* fix expert_weights_scale
* LGTM after whitespace fixes
* fix
* fix
* fix
* layers to layer_index
* enum fix
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Co-authored-by: Xuan-Son Nguyen <son@huggingface.co>
Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com>
