The HexBareissMathlib library is the Mathlib bridge for hex-bareiss. It
exposes the row-pivoted Bareiss determinant correctness theorems against both
Mathlib's determinant and the executable Leibniz determinant, building on the
no-pivot bordered-minor invariant in HexBareissMathlib.Bareiss and the
determinant correspondence in HexDeterminantMathlib.
Row-pivoted Bareiss determinant soundness, exposed against Mathlib's determinant for downstream Mathlib-side callers.
The row-pivoted Bareiss determinant equals the executable Leibniz
determinant on integer square matrices. Proven Mathlib-side by composing
bareiss_eq_mathlib_det with det_eq, so it holds outright (no sorry-bound
hypothesis) and is the preferred surface for downstream Mathlib-side callers.