Define/document a repeatable formula for building UIs to a debian file

[joco-nz]

With the shift in python to make local installs problematic we need to support UI developers in suppling an easily deployable version of their work. Debian .deb packages is the cleanest and most natural way to do this as we move to Debian 12 and beyond.

Defining a clear and reusable template with instructions for doing this will be key to support UI builders.