`handle_bitcoin_init_wallet_from_seed` derived the BIP-84 account extended
*private* key, stringified it, and imported `wpkh(xprv/0/*)` / `wpkh(xprv/1/*)`
into a Bitcoin Core descriptor wallet created with `disable_private_keys=false`
and an empty passphrase. That put a second copy of the node's spending key in
Core's `wallet.dat`, outside the daemon's Argon2 + ChaCha20-Poly1305 envelope.
That duplication into weaker protection was audit finding F-13 (High).
Deleted rather than rewritten watch-only (D-07b supersedes D-07/D-07a):
- No caller anywhere. Repo-wide search leaves exactly one occurrence of the
method name (its own dispatcher registration) and two of the symbol in code
(definition + dispatch call); every other hit is prose in docs.
- LND is the wallet the product drives. Across neode-ui/src every `bitcoin.*`
call is read-only status (getinfo/prune-status/onion); the wallet UI sends
via `lnd.sendcoins`.
- It never ran on archi-dev-box: no wallet named `archipelago` exists there,
and the one loaded wallet reports blank=true, keypoolsize=0, txcount=0.
- It was authenticated AND password-gated, so F-13 was key-at-rest
duplication, not an exposed endpoint.
No migration is performed and none is planned. This removes code, not wallets:
nothing on disk is touched, no funds move, no wallet.dat is modified. If a node
is ever found holding a wallet this handler created, that is a finding to
surface and stop on, not a trigger to auto-migrate.
`seed::derive_bitcoin_xprv` loses its only non-test caller and is retained
deliberately with `#[allow(dead_code)]` and a stated reason: it keeps its
existing test coverage and it is the derivation D-07c's deferred BDK cold vault
will need.
Records the evidence, the D-08/D-09 consequences and the D-07c deferral in
docs/security/KEY-03-SIGNING-POSTURE.md.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
