Stability: Atomic creation of entities + authorization policies

Description

Currently is the creation of an entity fails, then there are often partial entities left over - causing both orphaned data and instability in the server.

Goal

Creation of entities should be done in memory, with only a single save at the end.

Hypothesis

Having atomic creation of entities will

improve production server stability
reduce data without the proper relations set
improve developer effectiveness (less resetting of the database)

Must have scope

[ ] alkem-io/server#4102
[ ] alkem-io/server#4103
[ ] alkem-io/server#4104
[ ] alkem-io/server#4105
[ ] Authorization policy updates to be done in-memory and with a single save per boundary entity. Note: a space is a boundary, in that when saving a space it does not cascade to the subspaces in there.
[ ] alkem-io/server#4106

Stakeholders

Development QA

Design

To be build up from lower level entities. Spike can go last to derisk the rest of the work.

alkem-io / alkemio