Debian/Ubuntu installation should use deb822 .sources format

The apt package manager is moving away from the legacy .list format towards the new .sources format for repository configuration. The install script currently configures repositories using the legacy format. It should be updated to use the newer format, at least on systems that support it.

APT is moving to a different format for configuring where it downloads packages from. The files /etc/apt/sources.list and *.list files in /etc/apt/sources.list.d/ are replaced by files still in that directory but with names ending in .sources, using the new, more readable (deb822 style) format. For details see sources.list(5). Examples of APT configurations in these notes will be given in the new deb822 format.

Example .sources file for Docker repo:

Types: deb
URIs: https://download.docker.com/linux/debian
Suites: trixie
Components: stable
Signed-By: /etc/apt/keyrings/docker.asc

Locate the install script's Debian/Ubuntu APT repository configuration and review how supported systems are detected. Update the relevant path to use deb822 .sources files where supported, preserving compatibility for other systems; done means repository setup follows the requested format without breaking installation.