Wrap a random 32-byte message key with Argon2id+ChaCha20-Poly1305.
sqlite messages.plaintext is nonce||ciphertext; identity keys stay
plaintext. Empty/wrong passphrase fails closed. Ctrl-Q types CLEAR or
QUIT then Enter (Esc cancels).
/wipe overwrites the message log and VACUUMs; identity and friends stay.
/wipe-all deletes the data dir after confirm so the next open is a new person.
Neither runs without a typed confirm screen.