[RFE] Apptainer

[ben-auo]

Current situation

Apptainer is a Linux Foundation container engine but is not currently included: https://github.com/flatcar/sysext-bakery/releases

Impact

Prevents widespread use of Flatcar in HPC environments.

Ideal future situation

Please add support for Apptainer.

Implementation options

Executable SIF images could be stored in /opt/bin