Fix search hanging on production by correcting Pagefind file path

Problem: Search modal hangs on loading in production deployment,
but works fine locally.

Root cause: The Pagefind route handler was reading files from
.next/pagefind, which is not reliably accessible in production
deployments. The build script copies Pagefind files to
public/_pagefind for deployment, but the route wasn't using them.

Solution: Changed the file path in app/pagefind/[...path]/route.ts
from .next/pagefind to public/_pagefind. Files in the public
directory are always accessible and properly deployed.

This ensures search works consistently across both development
and production environments.

app/pagefind/[...path]/route.ts

@@ -8,7 +8,7 @@ export async function GET(
 ) {
   try {
     const { path } = await params;
-    const filePath = join(process.cwd(), '.next', 'pagefind', ...path);
+    const filePath = join(process.cwd(), 'public', '_pagefind', ...path);
 
     // Read the file
     const file = await readFile(filePath);