fix: wrap useSearchParams pages in Suspense for prerender

Next.js 15 static prerender bails out when useSearchParams is used
outside a Suspense boundary. Extract the hook-using component into
an inner child and wrap it in Suspense at the page root.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/app/(portal)/portal/verify/page.tsx

@@ -1,10 +1,10 @@
 'use client';
 
-import { useEffect, useRef } from 'react';
+import { Suspense, useEffect, useRef } from 'react';
 import { useRouter, useSearchParams } from 'next/navigation';
 import { Loader2 } from 'lucide-react';
 
-export default function PortalVerifyPage() {
+function PortalVerifyInner() {
   const router = useRouter();
   const searchParams = useSearchParams();
   const calledRef = useRef(false);
@@ -33,3 +33,17 @@ export default function PortalVerifyPage() {
     </div>
   );
 }
+
+export default function PortalVerifyPage() {
+  return (
+    <Suspense
+      fallback={
+        <div className="min-h-screen flex items-center justify-center bg-gray-50">
+          <Loader2 className="h-8 w-8 animate-spin text-[#1e2844]" />
+        </div>
+      }
+    >
+      <PortalVerifyInner />
+    </Suspense>
+  );
+}