Make the organization name its id, drop the mongo id

[fm3]

Proposing this change to the organization structure. This would also match the terminology already introduced in the webknossos-libs

display name → name
name → id
id - remove the mongoid completely

Blocked by voxelytics logs in loki.

#7687 should be deployed everywhere where voxelytics logs are stored for at least 12 weeks. Then we can proceed with this issue. From what I can tell that means after July 8, 2024 we should be safe