A new partition.conf was added in the calamares-settings-debian package. In that file, there is a line "luksGeneration: luks2", which is installing forky/testing systems that cannot be booted by grub, dropping user to the grub prompt. When partition.conf does not exist (as is in Trixie), this setting defaults to luks1. I read that grub has some support for unlocking luks2 partitions, however, I think it is not complete. This bug report has more information:
https://savannah.gnu.org/bugs/?55093.
The partition.conf file also includes a line "initialSwapChoice: none", which skips creating a swapfile on the installed live system. This is a change from Trixie which defaulted to creating a swapfile that was double or the same size as ram, depending on how much ram was installed in the users machine. The old behavior can be restored with "initialSwapChoice: suspend". I personally do not have a preference for the default choice of this setting. I decided to mention it, because I didn't notice an entry for it in the changelog, so I thought it might be an unintentional change. One data point I noticed while looking into this, is that the guided partitioning in Debian Installer creates a swap partition.