Models any aliased expression. E.g. `select exp as e ...` where the aliased node is the complete `exp as e` "expression" - `exp` is it's "wrapped node" and `e` is the alias. This will only ever be some kind of selection (dynamic-instantiation, JPA select-object syntax, an expression or a dynamic-instantiation argument). Each of these can be represented as a DomainResultProducer which is ultimately