I need a compact implementation of the WhatsApp Business API that lets me both send and receive messages from my application. The main traffic will be document files—PDFs and Word docs—so attachment handling must work flawlessly alongside plain text. A simple, well-documented module or microservice is perfect. It should: • Authenticate with the WhatsApp Business API and manage tokens or sessions • Expose an endpoint (or clear function) to push out messages with document attachments • Provide a webhook that captures every inbound message and returns the payload to my system in JSON • Log basic delivery/error events for quick troubleshooting Time is critical; I’d like to see a working proof of concept right away and a production-ready package shortly after. Let me know which language or framework you prefer (Python, Node.js, PHP are all fine) along with any configuration steps I must complete on the Facebook/Meta side so we can move fast.