[mithril] release 2412.0 changed the mithril-client command/subcommand structure

[TrevorBenson]

Describe the bug The snapshot download used to be called via mithril-client using command subcommand structures. The download was snapshot download, there was also snapshot list and snapshot show. All snapshot logic is now contained inside cardano-db, but has also been restructured so download is a direct subcommand of cardano-db (i.e. cardano-db download) while the show and list subcommands remain as part of snapshot.

The current scripts still use the old method of snapshot download which is being deprecated.

cardano-db
    download
    snapshot
        list
        show

Other commands like mithril-stake-distribution appear unchanged.

Additional context The scripts should use the updated structure to future proof for when full deprecation removes snapshot as a command and cardano-db download is the only method to download the database (snapshot).