deriveRPC fails on structures with Address

Description

deriveRPC has been changed to be recursive by default. Unfortunately, this breaks on Address. I didn't investigate, but AFAICT this happens because Address is a synonym for Constrained KindedAddress, which is a GADT, which deriveRPC doesn't support. And the check for existing instance either happens too late or doesn't work because it's a type synonym.

Steps to reproduce

data Foo = Foo Address Mutez
  deriving stock (Generic, Eq)
  deriving anyclass (IsoValue, HasAnnotation)

deriveRPC "Foo"

Prerequisites (if needed):

Expected behaviour

It compiles

Actual behaviour

"Unsupported constructor Constrained ..."

Environment

• morley-1.19.0, but I don't see why this wouldn't happen on master