improvement: docker infrastructure overhauled.

frontend/next.config.ts

@@ -1,6 +1,17 @@
 import type { NextConfig } from "next";
 
-// frontend/next.config.js
+function publicAppHostname(): string | null {
+  const url = process.env.NEXT_PUBLIC_APP_URL;
+  if (!url) return null;
+  try {
+    return new URL(url).hostname;
+  } catch {
+    return null;
+  }
+}
+
+const appHost = publicAppHostname();
+
 /** @type {import('next').NextConfig} */
 const nextConfig = {
   // Enable React strict mode
@@ -9,12 +20,19 @@ const nextConfig = {
   // Disable x-powered-by header for security
   poweredByHeader: false,
   
-  // Configure allowed remote image sources
+  // Configure allowed remote image sources (hostname derived from NEXT_PUBLIC_APP_URL at build time)
   images: {
-    remotePatterns:
-      process.env.NODE_ENV === 'production'
-        ? [{ protocol: 'https', hostname: 'yourdomain.com' }]
-        : [{ protocol: 'http', hostname: 'localhost' }],
+    remotePatterns: [
+      { protocol: "http", hostname: "localhost" },
+      ...(appHost
+        ? [
+            { protocol: "http" as const, hostname: appHost },
+            { protocol: "https" as const, hostname: appHost },
+          ]
+        : []),
+      { protocol: "https", hostname: "dyolink.com" },
+      { protocol: "https", hostname: "www.dyolink.com" },
+    ],
   },
   
   // Environment variables that will be available at build time