Make RT Dashboard real-time again

The RT Dashboard is currently not real-time. At most, we can discuss micro-batching.

The awesome live refresh works at most every 10 seconds, not on a shorter interval or even having a push-experience. This is not the maximum freshness expected from a real-time visualization.

I understand that refreshing dashboard widgets every second or less will come with a CPU usage penalty. But if the value is in updates at real time, make it possible to choose this.