Below is a known-good partitioning recipe similar to your use case.
It puts all of /, not just /boot, in a real partition.
I think the main difference is the start of the second stanza
61440 1000 100000000 lvm
while you have
100 1000 -1 xfs
There may be a bug in handling -1 as the upper limit;
hopefully you will be able to flush it out if so.
To simplify things, I'd stick with d-i alone for the moment
and then introduce kickstart if it is helpful.
Kind regards
Vince
d-i partman-md/device_remove_md boolean true
d-i partman-md/confirm_nooverwrite boolean true
d-i partman-md/confirm boolean true
d-i partman-lvm/device_remove_lvm boolean true
d-i partman-lvm/confirm_nooverwrite boolean true
d-i partman-lvm/confirm boolean true
d-i partman-lvm/vgdelete_confirm boolean true
d-i partman-auto-lvm/no_boot boolean true
d-i partman-auto-lvm/new_vg_name string linux
d-i partman-partitioning/confirm_write_new_label boolean true
d-i partman/choose_partition select finish
d-i partman/confirm boolean true
d-i partman-basicfilesystems/no_swap boolean false
d-i partman/mount_style select uuid
d-i partman/confirm_nooverwrite boolean true
d-i partman-auto/method string lvm
d-i partman-auto/expert_recipe string workstation : \
1024 50000 1024 ext4 \
$primary{ } \
$bootable{ } \
method{ format } \
format{ } \
use_filesystem{ } \
filesystem{ ext4 } \
mountpoint{ / } \
. \
61440 1000 100000000 lvm \
$defaultignore{ } \
$primary{ } \
method{ lvm } \
. \
2048 300% 65536 linux-swap \
$defaultignore{ } \
$lvmok{ } \
method{ swap } \
format{ } \
. \
20480 50000 20480 ext4 \
$defaultignore{ } \
$lvmok{ } \
method{ format } \
format{ } \
use_filesystem{ } \
filesystem{ ext4 } \
mountpoint{ /usr } \
. \
4096 50000 4096 ext4 \
$defaultignore{ } \
$lvmok{ } \
method{ format } \
format{ } \
use_filesystem{ } \
filesystem{ ext4 } \
mountpoint{ /var } \
. \
2048 50000 2048 ext4 \
$defaultignore{ } \
$lvmok{ } \
method{ format } \
format{ } \
use_filesystem{ } \
filesystem{ ext4 } \
mountpoint{ /var/log } \
. \
2048 50000 2048 ext4 \
$defaultignore{ } \
$lvmok{ } \
method{ format } \
format{ } \
use_filesystem{ } \
filesystem{ ext4 } \
mountpoint{ /tmp } \
. \
4096 50000 4096 ext4 \
$defaultignore{ } \
$lvmok{ } \
method{ format } \
format{ } \
use_filesystem{ } \
filesystem{ ext4 } \
mountpoint{ /opt } \
. \
10240 20000 100000000 xfs \
$defaultignore{ } \
$lvmok{ } \
method{ format } \
format{ } \
use_filesystem{ } \
filesystem{ xfs } \
mountpoint{ /data } \
.