chore: align ecosystem to Next.js 16.1.6 and v1.6.0, migrate to ESLint 9 Flat Config

lib/config.ts

@@ -23,6 +23,7 @@ function createConfig() {
     isTesting: target === 'testing',
     isDevelopment: target === 'development',
     feedbackEnabled: env.NEXT_PUBLIC_FEEDBACK_ENABLED,
+    gatekeeperUrl: env.GATEKEEPER_URL,
 
     baseUrl: env.NEXT_PUBLIC_BASE_URL,
 
@@ -146,6 +147,9 @@ export const config = {
   get infraCMS() {
     return getConfig().infraCMS;
   },
+  get gatekeeperUrl() {
+    return getConfig().gatekeeperUrl;
+  },
 };
 
 /**