Add images to Showcase section

Great project, thanks for all the work, I'm going to build one myself, but I was just wondering why the showcase section doesn't at least try to provide image previews?
It's not, you know, ***show***casing much right now.
From a visual design perspective, you could limit the height and keep it in a table.
Theoretically, you don't even have to host the images yourself (heresy, I know), but use the ones hosted on GitHub, theoretically you'd get dynamically sized images for free without the need for a server.

Here's a concept I made in 5 minutes in dev tools. It would make the section a lot more appealing and usable. The images are just normal `img` elements with `max-height: 6em`.

Start at the repository's Showcase section and review the attached visual concept, including the proposed image previews and max-height constraint. Add previews without making the section unwieldy, then verify that the showcase renders correctly and remains usable in its current layout.

Written by the indexing model from the issue text.