Support for unattended post-install configuration

[philipanda]

The problem you're addressing (if any)

The Qubes OS installer cannot currently run in a fully automated (unattended) mode.
Some configuration options required during post-installation are not read from kickstart.cfg, which makes manual input necessary.
References:

Reading from kickstart implementation: qubes.py#L175-L201

The list of required options: qubes.py#L60-L78

Existing issues

I've been searching for keywords like unattended, auto(mated), post-install, post, install(ation) but haven't found any title that would suggest to me it would tackle automating the post-install steps

The solution you'd like

Implement support for a fully unattended installation. Suggested way of doing it:

1. Ensuring all required settings are read from kickstart.cfg (qubes.py#L180

2. Modifying the initialize method (GUI and TUI) to set self.seen = True when all required settings are present (qubes_os.py#L641-L651

3. The existing configuration logic of the actual installation steps can be left unchanged (qubes.py#L203-L264

The value to a user and who that user might be

This would enable fully automated Qubes OS installations, useful for developers and testers who need unattended setups for continuous integration or large-scale testing.
It would streamline automated testing workflows that currently rely on installers that can be at most semi-automated due to the need to manually set and apply the post-installation settings.

Completion criteria checklist

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