(Wayland) Allow moving windows from one virtual desktop to another with a single action

KWin with Wayland allows for a window to appear on multiple virtual desktops simultaneously. The popup menu where users assign virtual desktops for windows currently does not let users move a window from one desktop to another directly. Instead, users need to enable the window on the desktop they want to move the window to and subsequently disable it on any other desktops. This patch adds a "CTRL+click" action that provides the moving behavior similar to what we have on X11.