Expense Tracker API

Build an API for an expense tracker application. This API should allow users to create, read, update, and delete expenses. Users should be able to sign up and log in to the application. Each user should have their own set of expenses.

1. Sign up as a new user.
2. Generate and validate JWTs for handling authentication and user session.
3. List and filter your past expenses. You can add the following filters:- Past week - Past month - Last 3 months - Custom (to specify a start and end date of your choosing).
4. Add a new expense
5. Remove existing expenses
6. Update existing expenses