nvidia repos failing on re-sync - Error: Task failed: ''NoneType' object has no attribute 'artifact_set_sha256''

Version
pulpcore 3.89.1
pulp_deb 3.7.0
Installed via container: quay.io/pulp/pulp:3.89.1

Describe the bug
Repeated syncs of the nvidia cuda repos fail with 'NoneType' object has no attribute 'artifact_set_sha256''

To Reproduce

Create the repo:

NAME="nvidia-cuda-24.04-amd64"
pulp deb remote create --name=$NAME --url="https://developer.download.nvidia.com/compute/cuda/repos/ubuntu2204/x86_64/" --distribution /
pulp deb repository create --name=$NAME --remote=$NAME
pulp deb repository sync --name=$NAME
PUB_HREF=$(pulp deb publication -t verbatim create --repository=$NAME | jq -r '.pulp_href')
pulp deb distribution create --name=${NAME}-bimonthly --base-path=${NAME}-bimonthly --publication $PUB_HREF

Note that the /pulp/content/$NAME/Packages file exists

Re-run a sync:

pulp deb repository sync --name=$NAME 
PUB_HREF=$(pulp deb publication -t verbatim create --repository=$NAME | jq -r '.pulp_href')
pulp deb distribution update --name=${NAME}-bimonthly --base-path=${NAME}-bimonthly --publication $PUB_HREF

Note that /pulp/content/$NAME/Packages has disappeared.

Re-run the sync pulp deb repository sync --name=$NAME and get the sync fail with 'NoneType' object has no attribute 'artifact_set_sha256''

Expected behavior
A new sync/publication/distribution update would not delete the Packages file and would complete successfully.

Additional context
Re-doing the sync as

pulp deb repository sync --name=$NAME --no-optimize

makes the repository usable again until the next sync happens that does not use --no-optimize

Start by reproducing the failure with the provided Pulp CLI commands against the listed pulpcore and pulp_deb versions, comparing a normal sync with one using --no-optimize. Trace the optimized re-sync and publication flow that removes Packages and later raises the NoneType error; done means repeated sync, publication, and distribution updates complete successfully without deleting Packages.