docs: document wallet integrity boundaries

src/lnurlcash/AGENTS.md

@@ -22,8 +22,9 @@ lnurlcash-kit directly.
 ```
 ops.ts / ops/    # flows: carve (exact-amount), mint, pay, receiveBearer,
                  # transfer (inter-mint); ops.ts is the façade
-storage/         # encrypted bearers + activity log, settings, backup,
-                 # nwcConnections, passkeySlots; storage.ts is the façade
+storage/         # encrypted bearers + activity log, owner-bound NWC,
+                 # passkey and trusted-mint records, settings, backup;
+                 # storage.ts is the façade
 keys.ts          # BIP39, LUD-05 linking key derivation, password wrap
 passkeys.ts + passkeyWrap.ts   # WebAuthn PRF wrap (same linking key)
 nostrBackup.ts + nostr/        # kind-30078 backup, NIP-44 self-encryption
@@ -38,8 +39,21 @@ test-utils.ts    # mock mint harness used by *.test.ts
 - Style: NO semicolons, 2-space indent, single quotes, `{braced}` imports
   without inner spaces — deliberately different from the rest of the app
   (eslint override); keep the tested core diffable against its lineage.
-- Storage: localStorage keys `sattle_*`; strict shape validation on read,
-  malformed entries dropped; read-modify-write under `withStorageLock`.
+- Storage: localStorage keys `sattle_*`; strict shape validation on read.
+  Credential, NWC, passkey, and trusted-mint records belong to the canonical
+  saved-key owner. Normal writes require that exact persisted owner; migration
+  of ownerless legacy records has its own proof-gated API.
+- Concurrency: read-modify-write uses `withStorageLock` where Web Locks are
+  available, but lock handoff is not a localStorage visibility barrier. The
+  trusted-mint repository reconciles from a durable IndexedDB commit mirror
+  before one successful localStorage write and before resolving. Its fallback
+  is local execution only, with no cross-tab serialization guarantee. Storage
+  events are wakeups, so listeners re-read current storage instead of trusting
+  `event.newValue`, including on clears.
+- Lifecycle: wallet transitions serialize create, restore, unlock, lock, and
+  forget. Activation completes proven-owner migration before exposing unlocked
+  state. Forget locks, drains NWC, clears runtime and owner-bound state, then
+  removes the saved key after biometric deletion succeeds.
 - Network: kit calls only; injectable transport/options so tests never
   touch the network. No WebSocket at import time (lazy `import()`).
 - Every module header comment explains the WHY, including failure models.