Update and begin using the preseed again for automated install

In the past, we set up a preseed file for semi automated installs. This is outdated by now both in content and in the fact that it is not currently used. It can also be improved to entirely automate the setup process to the point of not only specifying os install settings, installing packages, and cloning devcade, but also running setup scripts and config scripts maybe even asking the user to interactively answer questions to set env vars and settings right.

Locate the existing preseed file and review its current OS-install, package-installation, and Devcade-cloning steps. Then inspect the setup and config scripts and define which steps should be automated or require interaction. Done means a tested, agreed automated installation flow replaces the outdated unused process.

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