fix(frontend): allow localhost dev origins

Expands Next.js allowedDevOrigins to include localhost/127.0.0.1 to reduce dev proxy ECONNRESET when binding next dev to 127.0.0.1.

frontend/next.config.ts

@@ -1,7 +1,11 @@
 import type { NextConfig } from "next";
 
 const nextConfig: NextConfig = {
-  allowedDevOrigins: ["192.168.1.101"],
+  // In dev, Next may proxy requests based on the request origin/host.
+  // Allow common local origins so `next dev --hostname 127.0.0.1` works
+  // when users access via http://localhost:3000 or http://127.0.0.1:3000.
+  // Keep the LAN IP as well for dev on the local network.
+  allowedDevOrigins: ["192.168.1.101", "localhost", "127.0.0.1"],
   images: {
     remotePatterns: [
       {