GHSA-HM7R-C7QW-GHP6 fast-jwt accepts unknown `crit` header extensions (RFC 7515 violation)

Summary fast-jwt does not validate the crit Critical Header Parameter defined in RFC 7515 §4.1.11. When a JWS token contains a crit array listing extensions that fast-jwt does not understand, the library accepts the token instead of rejecting it. This violates the MUST requirement in the RFC. ---...