DeadCodeDetector: Handle more cases with unused ADT constructors

[jubnzv]

Consider an ADT with some unused constructors. If this ADT is not used as an argument of transition, its constructors will be reported as dead. Even if this ADT is a part of another ADT (which is also must not be used in arguments of transitions).

Minimal examples that illustrate the implemented changes:

type A =
| A1 (* A1 is unused, but we don't report it, because A is used in
        constructors of B, which comes from transition `foo`. *)
type B =
| B1 of A

transition foo(b : B)
end

type A =
| A1 (* Report A1, because it is unused and neither A and B are used in
        arguments of transitions. *)
type B =
| B1 of A

procedure bar(b : B)
end

Closes #1118