Plan and execute the migration from classical public-key cryptography (RSA, ECDSA, ECDH, DH) to NIST-standardized post-quantum algorithms (FIPS 203 ML-KEM, FIPS 204 ML-DSA, FIPS 205 SLH-DSA, draft FIPS 206 FN-DSA), defending against harvest-now-decrypt-later (HNDL) attacks and meeting CNSA 2.0, BSI, ANSSI, and EU CRA expectations. Use when inventorying cryptographic dependencies, selecting hybrid schemes, building a crypto-agility layer, or estimating PQC migration effort.