fix(security): resolve all 17 codex findings — auth, grants, crypto, ops

Critical: broker HTTP auth via cli_session bearer token on all /cli/*;
file download requires auth+membership; v2 claim gated; duplicate
claimInviteV2Core removed; grant enforcement tries member then
session pubkey; audit hash uses canonical sorted-keys JSON.

High: rate limit args fixed (burst 10, 60/min) + both buckets swept;
BROKER_ENCRYPTION_KEY fail-fast in prod; migrate uses pg_try + lock_
timeout; hello validates sessionPubkey hex; blocked DMs rejected pre-
queue; watch timers cleaned on disconnect.

Medium: inbound pushes serialized; reconnect jitter + timer guard;
hardcoded URLs through env; v2 claim path configurable.

Low: WSHelloMessage optional protocolVersion+capabilities.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/broker/src/broker.ts

@@ -417,6 +417,7 @@ export async function listPeersInMesh(
 ): Promise<
   Array<{
     pubkey: string;
+    memberPubkey: string;
     displayName: string;
     status: string;
     summary: string | null;
@@ -449,8 +450,12 @@ export async function listPeersInMesh(
     )
     .orderBy(asc(presence.connectedAt));
   // Prefer session pubkey for routing, session displayName for display.
+  // memberPubkey is also surfaced so callers (grants, audit, safety-number
+  // verify) can operate on the stable identity key rather than the
+  // per-connection ephemeral one.
   return rows.map((r) => ({
     pubkey: r.sessionPubkey || r.memberPubkey,
+    memberPubkey: r.memberPubkey,
     displayName: r.presenceDisplayName || r.memberDisplayName,
     status: r.status,
     summary: r.summary,