I hoped there might be a previous merged mr adding a gauge, but doesn't look like it.
As best I can tell, you need a new service, a new function/method in the api controller (to publish the data) - then add support in the embedded front-end app Javascript/CSS.
I'm not familiar with springboot, so I'm not sure if there are any generators to help, but it might be along these lines (for the java/rest part) - maybe someone else can chime in?
