shivansh-rajput-01/mern-expense-tracker ? reverse-engineered prompt

Build me a simple expense tracker web app where I can add income and expenses, see my current balance, and review my transaction history in one place.

I want a clean interface that feels easy to use on both desktop and mobile. The app should let me create, edit, and delete transactions, and clearly show totals for income, spending, and remaining balance. Please separate the client and server so it works like a normal full stack app, and make sure the data is saved instead of disappearing on refresh.

Keep the design modern but simple, with helpful empty states and basic validation so bad inputs do not break anything. If you need to look up current best practices or docs while building it, go ahead and do that. When you are done, make sure the app runs smoothly from the root project and everything is wired up properly.