fix: overhaul - lookup of behaviors at several places unified and sane usage of interface (schema) and marker

Fix (security): Attribute access to schema fields can be protected. This worked for direct schemas, but was not implemented for permissions coming from behaviors.
I'd use a try finally here, just to make it very clear that this always executes. I would also wonder what would happen here if in an enumerateBehaviors a ConflictError of some sort would be thrown.