Currently I only need the Keyboard Configurator application for the System76 Launch Keyboard.
There are no instructions on how to install the application via the CLI and I
serendipitously stumbled upon this with $ apt search system76 keyboard.
$ sudo apt install system76-keyboard-configurator
The support page lists what's in the box of every box of each Launch Keyboard.
The technical documentation gives a self-contained look and no marketing pizzazz from the product page (as if the marketing was even self-gratuitous in the first place) and details on how to basically disassemble the Launch Keyboard.
Lastly, the GitHub repo for the mechanical and PCB designs are not to be confused with the repo for the Keyboard Configurator application itself.