Standalone static guide (same pattern as /architecture/) covering how the
master seed entropy is drawn (explicit OsRng, sealed KeyGenRng allowlist,
degenerate-draw refusal, CSPRNG readiness ledger), how it is stored
(Argon2 + ChaCha20-Poly1305 envelope), the full derivation tree (HKDF
labels, NIP-06, LND aezeed one-way gate, second-order keys), what is NOT
seed-derived, every failure/fallback path, and the restore flow — in
paired layman/technical language. Linked from the Recovery-phrase card
in Settings → Backup. CSP-safe: no inline scripts.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
