shahnaj-sheikh/SGPT ? reverse-engineered prompt

Build me a ChatGPT style web app with sign up and log in, where each person has their own private chat history and can come back to previous conversations later. I want the assistant replies to stream in live while typing, with a stop generating button, and the chat should support markdown and code blocks so answers look good.

Use a React frontend and an Express and MongoDB backend, with secure email and password auth using cookies, not local storage. Please make sure users can only see and delete their own threads, and that the app handles errors cleanly, validates input, and feels safe by default.

I’d like it to work with an OpenAI compatible API, so I can switch between OpenAI and Groq with config if needed. Make it responsive on mobile, easy to use with the keyboard, and include the basic pages for login, register, and the main chat screen. If you need to look up current docs online, go ahead.