Is your feature request related to a problem? Please describe.
Running dartdoc from the command line is fine, but if you don't know that it exists, you're probably not going to organically discover it.

Describe the solution you'd like
A new command "Dart: Generate documentation" which finds dartdoc in the binary cache and executes it. Optionally, check for the existence of dartdoc_options.yaml and provide a sensible default if it's missing.

Describe alternatives you've considered
Continuing to use the command line and grumbling under my breath :)

Additional context