feat: add help for cli plugin

[tico88612]

Type of Change

• Bug fix
• New feature
• Breaking change
• Documentation update

Motivation and Context

Fix #387

Here's how I see the issue #387, though I'm not entirely sure.

Testing

• Tested locally
• Added/updated tests
• Added/updated docs

[jglogan]

@tico88612 Could you also rebase onto the current main? Our action runners got updated and you'll need the new workflows for your PR to build. Thanks!

[tico88612]

@jglogan I will update this later

[tico88612]

@jglogan I added the test and rebased to main.

[jglogan]

@tico88612 Looking at this one again...rather than preprocessing the arguments, could you try:

• Creating a HelpCommand.swift for help and add it to the subcommands of Application.swift?
• HelpCommand.swift would just call try? await Application.createPluginLoader() to get a plugin loader, and Application.printModifiedHelpText(pluginLoader)

I don't know if anyone's tried overriding the default help command this way but it'll keep all the nonstandard arg munging a bit simpler, and then the --help output should match the help output exactly.

[jglogan]

Niiiice! Thanks!

% container help
Warning! Running debug build. Performance may be degraded.
OVERVIEW: A container platform for macOS
USAGE: container [--debug] <subcommand>
OPTIONS:
  --debug                 Enable debug output [environment: CONTAINER_DEBUG]
  --version               Show the version.
  -h, --help              Show help information.
CONTAINER SUBCOMMANDS:
  create                  Create a new container
  delete, rm              Delete one or more containers
  exec                    Run a new command in a running container
  export                  Export a container's filesystem as a tar archive
  inspect                 Display information about one or more containers
  kill                    Kill or signal one or more running containers
  list, ls                List running containers
  logs                    Fetch container logs
  run                     Run a container
  start                   Start a container
  stats                   Display resource usage statistics for containers
  stop                    Stop one or more running containers
  prune                   Remove all stopped containers
IMAGE SUBCOMMANDS:
  build                   Build an image from a Dockerfile or Containerfile
  image, i                Manage images
  registry, r             Manage registry logins
VOLUME SUBCOMMANDS:
  volume, v               Manage container volumes
OTHER SUBCOMMANDS:
  builder                 Manage an image builder instance
  network, n              Manage container networks
  system, s               Manage system components
PLUGINS:
...