Adding a system tray to polybar

I think this could be done with some sort of Gtk Window, or if not then just a custom script through polybar.https://github.com/j-c-carr/dotfiles/labels/enhancement

Ideally there is a scroll bar for brightness and volume as well as something for wifi networks

No files or tests are named. Start by investigating how polybar can provide a system tray and whether a Gtk window or custom polybar script is viable. Done should include a system tray with controls for brightness, volume, and Wi-Fi networks.

Written by the indexing model from the issue text.