Allow customising of "extra" help

When I use certain things like choices or default values the outputted help looks quite convoluted to me. It would be nice to optionally hide that output of format it differently.

E.g. I have this:

Options:
  -l, --log-level  Set log level
      [choices: "silly", "verbose", "info", "warn", "error", "silent"] [default:
                                                                         "info"]
  -v, --version    Show version number                                 [boolean]
  -h, --help       Show help                                           [boolean]

Maybe something like this is nicer:

Options:
  -l, --log-level  Set log level (default: "info")
                   [ "silly", "verbose", "info", "warn", "error", "silent" ]
  -v, --version    Show version number                                 [boolean]
  -h, --help       Show help                                           [boolean]

Options:
  -l, --log-level  Set log level (defaults to "info" or use "silly", "verbose", "warn", "error", "silent")
  -v, --version    Show version number                                 [boolean]
  -h, --help       Show help                                           [boolean]

Options:
  -l, --log-level  Set log level (defaults to "info")
  -v, --version    Show version number                                 [boolean]
  -h, --help       Show help                                           [boolean]

Options:
  -l, --log-level  Set log level (info,silly,verbose,warn,error,silent)
  -v, --version    Show version number                                 [boolean]
  -h, --help       Show help                                           [boolean]

Start by locating the CLI help-generation entry point that formats choices, defaults, and boolean annotations; no specific file or test is named in the issue. Compare the requested output examples and determine the configuration shape before implementing it, with completion marked by tests covering hiding and alternative formatting of these extra details.