Recurrence 5 lookup certificate: LeadingSquare degree bound

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

theorem MazurTorsion.Kubert.OrderSevenBacktrackingCertificate.Internal.ResultantCertificate.recurrence5LeadingSquare_natDegree_le : Polynomial.natDegree recurrence5LeadingSquare ≤ 290

theorem MazurTorsion.Kubert.OrderSevenBacktrackingCertificate.Internal.ResultantCertificate.recurrence5LeadingSquare_coeff_high (n : ℕ) (h : 290 < n) : Polynomial.coeff recurrence5LeadingSquare n = 0