gh cli access to ICF

[ahpook]

Is your feature request related to a problem?

Related to #120 , it would be very cool to support ICF operations as a plugin/extension to the gh cli tool.

Describe the solution you'd like

If the internals were API-accessible one could imagine operations like:

> gh icf list
# shows list of forks
> gh icf mirror create apache/apache myforkname
# creates a private mirror of apache/apache
> gh icf mirror delete myforkname
# are you sure you want to delete this fork?

and potentially other operations.

Describe alternatives you've considered

No response

Additional context

No response