feat: add nvfp4 quantization (#47883)

* feat: add nvfp4 quantization

Signed-off-by: David Holtz <david.richard.holtz@gmail.com>

* Update docs/source/en/quantization/nvfp4.md

Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>

* Update docs/source/en/quantization/nvfp4.md

Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>

* docs: point nvfp4 overview link at kernels-community

* fix: remove unused global and unittest call

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Signed-off-by: David Holtz <david.richard.holtz@gmail.com>
Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>
Co-authored-by: Cyril Vallez <cyril.vallez@huggingface.co>