Add MacPorts

[rat-moonshine]

Add MacPorts support in-contrast with Moonshine-IDE/Moonshine-IDE#921.

[JoelProminic]

This installation will probably trigger an authentication prompt. See this comment for an option for triggering a GUI prompt from macOS instead.

This question gives some other options, but I'd rather not use third-party tools like cocoasudo.

[rat-moonshine]

It appears the MacPorts distributes as PKG-installer mainly. However, they also offers source installation which involves some client-side command-run/setup ways.

https://www.macports.org/install.php - Source Installation section details the process. This might be good idea to give this a test in a fresh Mac system that doesn't hold any pre-installed Xcode or Command Line Tools - to ensure on install dependencies.