Allow markdown and rich content within modal inputs

[VortexHero]

Modal right now have two text input styles: Short and Paragraph. I propose a new Markdown/Rich Content style that allows users to input markdown and other rich content on Discord (such as channel links, role tags, and user tags) in a modal.

Also, having a separate message component input for one/multiple channel links, role tags, and user tags would be very useful. (Similar to some Application Command Options.)

[vvito7]

Same as #4492