AI Full Stack Engineer Assignment

I have prepared a concise technical exercise that covers the complete workflow of a modern web application, from database layer to browser. The specification document is already written and will be shared immediately after we start; please follow it exactly and return a fully working solution... (Budget: ₹600 - ₹1500 INR, Jobs: Full Stack Development, J2EE, Java, MongoDB, Node.js, NoSQL Couch & Mongo, PostgreSQL, SQLite)