Function cardinality_parity_seams 

pub fn cardinality_parity_seams(
    num_vars: usize,
    clauses: &[Vec<Lit>],
) -> CardinalitySeams

Compute the CardinalitySeams of a fused instance: for every pair of variables interchangeable in some recovered cardinality group, test whether swapping them is a model-set symmetry ([SemanticSymmetry]) — joint if so, a seam if not. Pair-budget-bounded (a partial joint set still yields sound symmetry breaks).