React Todo List

The goal of this exercise is to create a working todo list with persistent data storage.

To start with, we have a styled todo list that supports adding todos. We also have premade styles for completed todo items. Although there's no working mechanism for "completing" a todo.

Requirements

1. Clicking on a "Submit" button should add item to the list (if it's not empty).
2. Clicking on a todo item should toggle the "checked" state.
3. Checked items should sink to the bottom of the list automatically
4. Add hidden timestamps to todos (created_at, completed_at), these will be used for sorting

• The active todos should be sorted by created_at descending
• The completed todos should be sorted by completed_at ascending