This is a tiny bar at the left of the taskbar where you can put
your most used apps to launch them with a single click. In a way,
it's another replacement for the Launcher, in addition to the app
menu. Unlike the launcher and the menu, it's not meant to be the
primary way to launch apps; it's only a faster way to launch a few
most often used utilities.
I originally thought I would do this inside WindowServer, but let's try to
make it as a standalone app that communicates with WindowServer instead.
That will allow us to use LibGUI. :^)