Reorganize commands (user facing + directory structure)

[rsek]

aside from renames, includes some additional description. /progress and /clock are now collapsed into single commands, but i've also retained the command group versions in separate files; once discord has a more sensible display for subcommand groups, i may bring them back in that format (mainly so i can better annotate the nuances of the individual progress/clock types)

also resolves #37

user command organization:

directory structure:

[rsek]

rebased with #27

[rsek]

rebased from main, now that #27 has been merged

[rsek]

resolves #37