Feature Request - Extra Dot Data

I have a data set where I have a set of known X & Y values but sometimes would like to draw a dot at an X value between 2 of my fixed points for which I may not have the exact Y value.

Similar to the extraLinesData for drawing vertical lines it would be super to have a similar parameter for extraDotData which will then take an X (or Y) value and draw a dot at the corresponding point on a line.

Currently a draw a vertical line at the given X value but a dot would be even better!

Maybe I'm missing a way to do this already?

Start by tracing the line chart's existing extraLinesData API and how it maps an X or Y value onto a line. Define the extraDotData input and its corresponding-point behavior, then verify that a dot is drawn at the requested position without changing existing line rendering.

Written by the indexing model from the issue text.