Allow Immich to run as a non-root user/group to enable sharing with photos stored in host datasets, file shares. Suggest apps:apps by default like other TrueNAS applications, but allow to be configurable for access to photos mounted from host datasets.
From the Immich documentation: immich.app/docs/FAQ/
You can change the user in the container by setting the user argument in docker-compose.yml for each service. You may need to add mount points or docker volumes for the following internal container paths:
immich-machine-learning:/.configimmich-machine-learning:/.cacheredis:/data
The non-root user/group needs read/write access to the volume mounts, including UPLOAD_LOCATION and /cache for machine-learning.