`pqcrypto-classicmceliece` is unmaintained: upstream PQClean project being archived

This crate provides Rust bindings to the Classic McEliece key encapsulation mechanism via C implementations from PQClean. The PQClean project is being archived in or after July 2026 see PQClean/PQClean604, after which no further security patches or bug fixes will be applied to the upstream...