HomeKit API enhancement request - provide a clean way to know whether a scene is 'active'

There is currently no way to easy way to tell whether an HMActionSet is 'active' without reading the individual characteristics - because each of these reads is an independent, asynchronous process, this check can be delayed, and it is often error prone.

Adding a simple state to read and track this information, similar to the value of a characteristic, would simplify a significant burden. A callback notification to be alerted to changes in this state would also be outstanding.