{"service":"WhatsApp Webhook Relay","version":"2.0.0","endpoints":{"GET  /whatsapp/webhook":"Meta verification","POST /whatsapp/webhook":"Meta incoming messages","GET  /messages/poll":"Long-poll for pending messages","POST /messages/ack":"Acknowledge received messages","POST /messages/send":"Send a message via Cloud API","GET  /messages/stats":"Queue statistics","GET  /health":"Health check"}}