Proposal: Encrypted Seedless Inheritance for P2QRH
Problem: P2QRH assumes owner has seed. For inheritance, heir has only paper. Raw ML-DSA key is 2560 bytes (~3413 chars) - too big for one QR and insecure if stolen.
Construction:
1. PQ-Seed = 90 bytes entropy (120 chars base64), expandable via SHAKE256 to any PQ private key.
2. backup = salt(16) + XChaCha20( Argon2id(password,salt), PQ-Seed ) 104 chars Base58, fits one QR.
3. Print one QR.
Heir flow: password + QR → PQ-Seed → private key → spend bc1r.
Benefits: 1 QR for all PQ algos, no pubkey exposure until spend, factor separation, no consensus change.
This is essentially BIP-38 for P2QRH, but using a 90-byte seed expandable via SHAKE256 to fit ML-DSA into one QR for inheritance.
Should we add this as Wallet Considerations to BIP-360?