Makefile/justfile or similar

[JakeStanger]

Is your feature request related to a problem? Please describe. Now that Ironbar's installation process is potentially more complex than before (#683), and likely to continue that way as additional bits make their way in, packaging gets more complex and the work has to be duplicated for each format.

Describe the solution you'd like It would be useful to offer a standardised process in the form of a job-helper script, make or just would be good candidates for this.

Describe alternatives you've considered Not sure yet.