For MAKE_ISO=yes builds, squashfs, kernel, initrd, manifests, and sizes
are now placed directly into config/iso-dir/iso-root/casper/ during the
build rather than creating livecd.* intermediates that get linked as
for-iso.* files and then copied into casper/ by isobuild.
This stops publishing the intermediate livecd.* artifacts so that only
livecd.*.iso and livecd.*.netboot.tar.gz are published for ISO builds.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
By placing the kernel in minimal, we can achieve the following
improvements:
1. Space savings - there are redundant packages present in the ship-live
pool and in the live layer. Adding the kernel to minimal means that
the kernel is already in the live layer, and we don't then also need
it in the pool.
2. Time savings - informal vm testing suggests more than a minute
improvement to have the kernel preinstalled over installing it at
runtime.
As always, there is a cost tradeoff:
1. If a different kernel is desired, we need to be able to remove this
preinstalled kernel. Relevant curtin and subiquity changes are
already landed.
2. When installing that other kernel, it'll take longer than today due
to still needing to install a kernel at runtime + the time cost of
removing the preinstalled kernel.
