Full-Stack solution with user login and registration functionality

Hi there!

For this challenge I decided to go with the full-stack project! I made it using Express for the backend hosted on Heroku, Mongo for the database hosted on MongoDB Atlas, and React for the front-end hosted on Github Pages.

It has user functionality, meaning you can create an account in which you can save your todo list. I tried to make the authentication part on the server following security standards for storing passwords, hashing them along with a salt and a pepper.

It also has a theme selector for dark and light mode, which is saved locally on the browser so it remembers your preference on reload.

Sometime in the future I may try to implement reordering the list, but that maybe would require some changes on the structure of the database.

I would appreciate any feedback! Thank you.