refactor(gateway): harden proxy client ip resolution

src/gateway/openresponses-http.ts

@@ -55,6 +55,7 @@ type OpenResponsesHttpOptions = {
   maxBodyBytes?: number;
   config?: GatewayHttpResponsesConfig;
   trustedProxies?: string[];
+  allowRealIpFallback?: boolean;
   rateLimiter?: AuthRateLimiter;
 };
 
@@ -343,6 +344,7 @@ export async function handleOpenResponsesHttpRequest(
     pathname: "/v1/responses",
     auth: opts.auth,
     trustedProxies: opts.trustedProxies,
+    allowRealIpFallback: opts.allowRealIpFallback,
     rateLimiter: opts.rateLimiter,
     maxBodyBytes,
   });