[monitor] Finalize the publisher widget

The port-ID spinbox on the right should show a tooltip explaining what it is, or it should be located on the left of the data type which would make its purpose clear because port-IDs always go below data types separated by a colon.
The field addition buttons at the bottom need to be reworked as we discussed.
Scrolling the mouse wheel while hovering will both change the knob position (which is good) and scroll the monitor view (which is bad)

Ideally, pressing ESC or some other well-defined shortcut while focused on the publisher widget should automatically disable it (uncheck the Enable checkbox).
Clicking the label here should also work as if the checkbox was clicked:

Only "The field addition buttons at the bottom need to be reworked as we discussed." is not done