Interactive Data Markers
Interactive markers can be added to a Smith chart using the function datamarkers(sc::SmithAxis, gp::GridPosition). sc is your SmithAxis block and gp is a GridPosition where the interactive widget will be placed—this can be a position like fig[1, 2] or GridLayout.
Add marker: Double-click on a plotted line or scatter point.
Remove marker: Double-click on an existing marker.
Move marker: Drag it using the left mouse button.
