[Pt.1] Remove EntityType

[arnoweiss]

The Entity-SME currently requires to use the EntityType attribute which can bei either "CoManagedEntity" or "SelfManagedEntity", signifying whether the referred Asset has its own AAS.

Here's the issue:

Someone referring to an asset (for instance in a BOM) will not always know if the referred Asset has an AAS or not. There's no way to be sure that an Asset has no AAS. That means everyone modeling an Entity is forced to make a definitive statement which (in most cases) can not be made definitively.

[BirgitBoss]

This is true. But if you choose CoManagedEntity you need to provide the information of the Entity within the submodel itself by adding corresponding statements. But it was not yet discussed what happens if the information for the entity is handled in a different submodel.

Discussion 2023-11-23 in Workstream AAS:
Alternatives:

• set entityType to optional
• extend enum with value "UNKNOWN"
• adjust description of enum values EntityType
• set attribute entityType to deprecated

to be considered:
Constraint AASd-014: Either the attribute globalAssetId or specificAssetId of an Entity must be set if Entity/entityType is set to "SelfManagedEntity". Otherwise, they do not exist.

Two options in case of CoManagedEntity:

• in the BOM containing this Entity-Element via statements
• in another Submodel of the same AAS
  - as part of the Technical Data of the overall asset
  - special submodel but it cannot be the technical data submodel
  - a statement can be used with a ReferenceElement that gives information where to find this information

Decision:
make entityType optional

• Change Constraint to:
  Constraint AASd-014: Either the attribute globalAssetId or specificAssetId of an Entity must be set if Entity/entityType is set to "SelfManagedEntity".