shaikiqbal6280/sample_mern_app ? reverse-engineered prompt

Build me a simple MERN app that feels like a real starter project, with a clean frontend, a Node and Express backend, and MongoDB for storing data. I want something I can run locally right away, with basic setup for environment variables, a clear way to start both sides, and a simple user flow that makes sense for a demo app. Please include a few common features like adding, viewing, updating, and deleting records, plus a nice looking interface that is easy to use. If it helps, keep the design minimal and modern, and make sure the code is organized so I can expand it later. Look up current docs online if you need to, and use sensible defaults so the app works without me having to figure out a lot of configuration.