SpaceAbout: authorization tidy up + mutations

[techsmyth]

Description

As a user I want a robust application
As a developer I want a clean conceptual model that is easy to maintain

Acceptance criteria

• Add mutations to allow joining / applying to a space not via roleset
• Update authorization to that if a user can see the Space, then the user has READ privilege on SpaceAbout that cascades. Remove all privilege rules that grant READ_ABOUT to READ within Profile entity tree. Grant READ_ABOUT on Space, not in any other place.

Additional Context

This issue does a second phase after the client is updated to get the information via spaceAbout

Areas that will be affected

To be added during the refinement