introduction to DaVinci in Run 3

[goi42]

The current lesson just links to the DPA documentation, which includes only a highly technical description of DaVinci in Run 3. (I've suggested that some more introductory material be included, but this is semi-independent of the need for a Starterkit lesson.)

As it stands, there's no accessible intro to Run 3 DaVinci or even a succinct description of the relevant changes.