Sealed box decrypt: extract ephemeral public key and nonce, then open with recipient's secret key.
Input format: ephemeralPubKey(32) || nonce(24) || ciphertext.
ephemeralPubKey(32) || nonce(24) || ciphertext
The sealed message produced by sealedBoxEncrypt.
The recipient's 32-byte Curve25519 secret key.
The decrypted plaintext bytes.
If the sealed data is too short, or decryption/authentication fails.
Sealed box decrypt: extract ephemeral public key and nonce, then open with recipient's secret key.
Input format:
ephemeralPubKey(32) || nonce(24) || ciphertext.