offline-distrosync compatible subcommands

[kontura]

Aliases for offline-distrosync and offline-upgrade don't match the dnf4 commands.
It basically changes dnf offline-distrosync download -> dnf5 offline-distrosync and discards the rest.

We do have all the functionality so I think we could build the aliases to (more or less) fit.

Something like:

['offline-distrosync']
type = 'command'
attached_command = 'distro-sync'
group_id = 'commands-compatibility-aliases'
complete = true

['offline-distrosync.download']
type = 'command'
attached_command = 'distro-sync'
complete = true
attached_named_args = [
  { id_path = 'distro-sync.offline' }
]

['offline-distrosync.log']
type = 'command'
attached_command = 'offline.log'
complete = true
...

Originally posted by @kontura in #1280 (comment)

[kontura]

Looks like this got reported twice: #1343 and its already completed.