Provide ways to determine last forward flows of an individual repo's dependencies

[mmitche]

While it is pretty easy to determine which version of the VMR an individual repo depends on (what was the latest backflow), some devs have wanted to make one additional hop and ask which sha of an individual repo that corresponds to. For example:

dotnet/aspnetcore depends on sha 12345 of VMR for dependencies A, B and C.

Make the following connection and provide the info:

A was produced in the VMR from runtime
B was produced in the VMR from arcade
C was produced in the VMR from efcore

Last FF for runtime was abcd
Last FF for arcade was efab
Last FF for efcore was 7890

dotnet/aspnetcore has dependencies on:
- runtime abcd
- arcade efab
- efcore 7890

It would be good to show this in both BarViz and darc