Hybrid decapsulate — recovers the combined shared secret using our private keys and the sender's ephemeral data.
ML-KEM security level (512, 768, or 1024).
Our X25519 private key (hex).
Our ML-KEM secret key (hex).
Sender's ephemeral X25519 public key (hex).
ML-KEM ciphertext from the sender (hex).
Hybrid decapsulate — recovers the combined shared secret using our private keys and the sender's ephemeral data.