Improve consistency of system-reinstall-bootc output

[ckyrouac]

Spawned from #1355 (comment).

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We probably want to make the whole output more consistent/formatted.

One possibility here is basically how Github Actions/Ansible and other things do it with clearly delineated "tasks" that have their own description.
(We could probably get a double win by doing this for install.rs too)

[jcpunk]

I'd add that machine parseable would be handy.