fix: honor Node all-address DNS lookup for HTTP webhooks

api/src/open-api/open-api.protocol.ts

@@ -1,5 +1,14 @@
 import { createHash, createHmac } from 'node:crypto';
 import { HttpException } from '@nestjs/common';
+import type { LookupFunction } from 'node:net';
+
+/** Keep the validated address pinned while honoring Node's all-address lookup contract. */
+export function pinnedWebhookLookup(address: string, family: number): LookupFunction {
+  return (_hostname, options, callback) => {
+    if (options.all) callback(null, [{ address, family }]);
+    else callback(null, address, family);
+  };
+}
 
 /** v1 compatibility: an absent parsed body hashes as {}, never try alternate hashes. */
 export function openApiBodyHash(rawBody: Buffer | undefined, body: unknown) {