- Create src/timmy/identity module with KeyVault class
- Implement Ed25519 key generation for Nostr identity
- Encrypted at-rest storage using AES-256-GCM + PBKDF2
- Support: store, load, list, delete, passphrase rotation
- Add comprehensive pytest suite (7 tests, all passing)
This is the foundational cryptographic key management layer for
Sovereign Identity: local-first, passphrase-protected, ready for
Nostr (nsec) and future Bitcoin/secp256k1 support.
Closes#469
b30a42d72e