* split play-button into container and component
* revised sound library tile:
* play button in upper right
* smaller sound icon (make the tile less loaded)
Play button doesn’t have a ‘touch-outside’ listener to stop sounds. That seems to be ok as other events cause the sound to stop.
Both handleClick and handleMouseDown are needed. Must use handleMouseDown for `preventDefault` to skip setting focus on the item. handleClick is needed to prevent the Click from propagating to the item and selecting it.