Use OpenSSL_MAC and OpenSSL_MAC_CTX wrappers together with
OPENSSL_TRY to replace manual EVP_MAC resource management in
KMAC::sign(). This eliminates manual EVP_MAC_free/EVP_MAC_CTX_free
calls in every error path.
Add a LibCrypto::Authentication::KMAC helper over OpenSSL.
Add keygen/import/export logic into WebCrypto.
Register KMAC128/KMAC256 operations with SubtleCrypto.