Module implication 

Reified implication constraint: antecedent = a → consequent ∈ allowed.

Encodes the gestalt rule “if variable X takes value a, then variable Y must be drawn from the bitset allowed.” Both variables share the same Domain::Value type. Used by recognizer-tier CSPs to enforce things like “if AltMode = TokenDispatch, all child engines must be one-pass-eligible.”

Structs

ImplicationConstraint

antecedent = trigger → consequent ∈ allowed.