This is a simple port of the mlir::CallGraphNode with llzk::CallGraph as a friend class, for mlir::CallGraphNode has a private constructor and can only be constructed by mlir::CallGraph
Matches and optionally captures a constrainref base value, which is either a field read or a block argument (i.e., an input to a @constrain or @compute function)
Produces errors if there is an inconsistency in the various attributes/values that are used to support affine map instantiation in the Op marked with this Trait