Fixes #1585

I have to confess, that I did not check every change in the unit test workflow files,
so they should probably be looked again closely. But I think it should have done the right thing.
Or at least how I envisioned it.

no typing =>

• only _Untyped class with _Untyped properties
• nullability according to required status

full typing =>

• same _Untyped class as above
• but marked as @Deprecated with a replace hint for the typed class (works in the IDE),
• additionally a typed class with each property as typed and untyped version
• all properties nullable, with runtime checks that
  • not the typed and untyped is set both for one property
  • one of the two is set for required properties

partly typing =>

• same _Untyped and typed class as above
• for inputs that have no type declared only the _Untyped property is added
• the properties that are only untyped have the nullability according to required status, also in the typed class