Drop jQuery From Project Pages & Move Gallery to New HTML <dialog>

[vkoves]

I'm using jQuery for some pretty basic stuff (the mobile menu, and the overlays) that I can handle via native JS, improving performance.

The overlays can also use the new HTML <dialog> element (see MDN - dialog) to keep it accessible with less code 🎉

[vkoves]

PR #67 started this by removing jQuery from the default layout, and moving it to just individual project pages