Design UI to manage tournament description and rules

[L-Mario564]

In the tournament settings page, the user must be able to write the tournament's description and rules, both supporting markdown syntax.

A toolbar should be provided for standard markdown shortcuts (headings, bold, italic, quote, inline code, block of code, link) and also be able to provide the ability to set the color of the text to primary-500 or any 500 shade of the Tailwind colors, which could be done by wrapping the selected text like so: <span class="{color}">{text}</span> (and limit the classes that can be passed to the class attribute to avoid possibly issues with other classes).

The user must be able to toggle between the markdown being written and the markdown once it's parsed (a preview of what's being written).