related to #94 (closed)
This is a proposal to no longer use pseudonyms to link contacts to subjects. Contacts are still kept in a spearate database, but has a subject_id much like would be used in a regular ForeignKey.
The main benefit is that settings.CASTELLUM_DOMAINS and sync_domains are no longer required, which is one thing less to learn for admins. From another perspective, this means that pseudonyms are only used for participation requests, which also is a more concise concept IMHO.
The migration still needs settings.CASTELLUM_DOMAINS, so it can only be removed once the migration was executed.
The only place where we exposed contact pseudonyms was in the monitoring logs. This now also uses subject_id, exposing slightly more information than before. I think this is actually a good thing because the previous string was pretty much useless.