Review ECMWF GRIB file virtualization

[maxrjones]

I'm a co-author on the ECMWF-oriented EGU abstract "Virtual Zarr for Ensemble Prediction Systems: VirtualiZarr Custom Parsers for Cloud-Native GRIB Access". Opening this issue to track their review request of https://huggingface.co/datasets/E4DRR/gik-ecmwf-par.