The first tile of a layout is its largest, and the place for the window being
worked on. `komorebic promote` moves the focused window there, with the windows
that were before it each moving one tile on; `promote-swap` swaps it with the
window that has the first tile, and from the first tile swaps it back with the
window it was last swapped with; `promote-window left|right|up|down` promotes
the window on that side of the focused one; and `promote-focus` gives the focus
to the first tile and moves nothing.
The grid layout has no largest tile, so the four do nothing there.
The vm-commands sweep gains the four.