This script centralizes state for the SlateWithManipulators prefab, allowing the various elements of the prefab to participate in statefulness without taking any direct dependencies on one another. Canonically, all interactable elements within the prefab will take references to this signaler, which they will use both to subscribe to the WhenStateChanged event and to set the state when appropriate. In this way, when one interactable element is selected, it can set the state and thereby notify other interested elements that the prefab as a whole, in a sense, has been selected; the other elements can then respond to this signal as appropriate, typically by becoming disabled for the duration of the selection. This signaler can also be used by external logic to set state for the entire prefab, for example to set the prefab to Idle when no interactors are nearby, though this is not part of the prefab's default behavior.