Demonstrates Streams with consumer groups for message queue
functionality in Vercel Functions. Includes:

- Contact form message producer (POST /api/messages)
- Consumer group message processor with XREADGROUP and XAUTOCLAIM (GET /api/messages)
- Message acknowledgement endpoint (DELETE /api/messages)
- UI components for form submission and message processing
- valkey-glide client integration with proper error handling

`serverComponentsExternalPackages` moved out of `experimental` in
Next.js 15+

getMetadata is not compatible with client components