Missing default systemd-boot load entry (wrong boot order) #1777
Description
When using bootc install to-disk --composefs-backend --via-loopback bootable.img --filesystem ext4 --wipe --bootloader systemd first boot works fine since only the following loader entry exist.
/boot/loader/entries/bootc-composefs-1.conf
However following bootc switch or bootc update the system fails to update properly due to there being no default in /boot/loader/loader.conf and sd-boot preferring smaller numbers/strings.
The bootc update process creates:
/boot/loader/entries/bootc-composefs-0.conf (current/old)
/boot/loader/entries/bootc-composefs-1.conf (new/staged)
However systemd-boot always boots 0.conf first (it also has sort-key 0 in the file.)
This can be reproduced and fixed on the amazing bootcrew images linked in #1735 via the following command:
mount /dev/vda1 /boot && echo 'default bootc-composefs-1.conf' > /boot/loader/loader.conf && umount /boot