Feature request: support HATS catalogs with hlx-cli

[hombit]

It would be great if hlx-cli could be used to create HATS catalogs and read them (or read any healpix-sorted parquet datasets), for example for density MOM generation.

[fxpineau]

What about an other CLI heavily based on sort, hcidx and qhcidx of hpx-cli but having parquet support?

E.g., I also implemented those 3 sub-commands for VOTables, but in a dedicated VOTable CLI, see vot-cli (the README may not be up-to-date).

[hombit]

Sounds good to me, and VOTable tool also looks very cool.