perf: speed up kernel checking of non-commutative, semiring, and field certificates

This PR extends the kernel-reduction variants of the `grind` ring certificates to non-commutative rings, commutative semirings, and fields. `Poly.insert`, the non-commutative monomial and polynomial operations, `Expr.toPoly_nc`, `Expr.toPolyC_nc`, and `Expr.toPolyS` gain recursor-based variants, and the certificates for these structures, including those of `Init.Grind.Ring.FieldSolver`, evaluate them and compare polynomials with `Poly.beq'`.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>