Position of a participant’s video within the layout canvas.
'auto' — Automatically positioned by the layout engine.`reserved-${number}` — A reserved slot in the layout (e.g., 'reserved-0').`standard-${number}` — A standard slot in the layout (e.g., 'standard-1').'off-canvas' — Participant is not visible in the layout.'playback' — Playback position for media streams.'full-screen' — Participant occupies the entire canvas.