Expert Developer for Whatsapp Ai Auto-Reply Bot

I need a developer to deliver a functional MVP of a WhatsApp bot with automated AI-powered replies. The project should include integration with WhatsApp Web, with QR code login and persistent session support, as well as processing incoming messages and sending automatic responses.

It should also include integration with the Openai api for intelligent replies, along with a standard fallback response whenever no ai key is configured. The system must provide a rest api with status and health check routes, plus an endpoint for sending messages.

Configuration should be handled through environment variables in a .env file, with a well-organized Node.js and Express structure separating services, routes, and utilities. I also expect execution logs and clear installation and running instructions.

The expected stack is Node.js, Express, whatsapp-web.js, Axios, dotenv, and logging. The final delivery should include the project running locally, documented source code, and a README with step-by-step usage instructions.