udmodz0/whatsapp-auth-api ? reverse-engineered prompt

Build me a simple WhatsApp OTP API in Node.js that lets me connect a WhatsApp account with a pairing code, send OTP messages through WhatsApp, and manage linked bots from easy HTTP routes. I want endpoints for pairing, sending a message or OTP with a copy code button, deleting a bot, and checking health so I can see which bots are online.

Make it ready to run locally and on Vercel, with sessions saved so the bot can reconnect after restart. If it needs current docs or a small library detail, look it up online and use the latest approach. Please keep the setup straightforward, add clear error handling, and make it easy to configure with environment variables for the GitHub session storage and anything else needed.