busctl: convert to the new option and verb parsers

busctl: convert to the new option and verb parsers

The conversion doesn't work great, because some of the verbs take many
arguments and the first column is extermely wide. So similarly to
kernel-install, I dropped the sync of column widths. This allows the
help for options to use most of the available space.

-C/--capsule is now documented, fixup for
 00431b2b66cb59540deda4ea018170a289673585.

Verb functions are renamed to match verb names.

The missing first param is added to the synopsis of "wait".
It now matches the man page.

Co-developed-by: Claude Opus 4.6 <noreply@anthropic.com>