Recurrence 4 lookup certificate: LeadingSquare degree bound

This is a checked coefficient-lookup shard for the fourth pseudo-division recurrence in the order-seven certificate.

theorem MazurTorsion.Kubert.OrderSevenBacktrackingCertificate.Internal.ResultantCertificate.recurrence4LeadingSquare_natDegree_le : Polynomial.natDegree recurrence4LeadingSquare ≤ 328

theorem MazurTorsion.Kubert.OrderSevenBacktrackingCertificate.Internal.ResultantCertificate.recurrence4LeadingSquare_coeff_high (n : ℕ) (h : 328 < n) : Polynomial.coeff recurrence4LeadingSquare n = 0