fix for partial hand restore after hydra goes inactive

This is a very quick fix to help restore the hands when the hydra controllers go inactive.

The problem was that the "restore" operation on the hands would make sure that the animation priority matched, but would then clear the state's animation priority to zero, which would cause subsequent calls not do anything (priority no longer matched).

A more long term solution is to treat the hydra like any other animation and blend in/out when it transitions in/out of activity.