Summary: while apparently not a core part of Git/Github, the combination of Git Extensions and TortoiseGit does the job
Use case: within Windows/File Explorer, I want to see the status of my files relative to the Git repo, e.g. Added, Changed, Deleted, Unchanged
I googled…[file overlay icons github]
I am very used to explorer icons in other source control systems, e.g. svn/Tortoise, and have taken them for granted. However, there seems to be a lot of huffing and puffing around the subject on the Git forums, with the opposite camps of “What on Earth do you want that for?” and “it is mad this is not available by default”.
This Stackoverflow post talks about [“GitExtensions is awesome for the true git experience. TortoiseGit obscures Git, forcing it into a “simple” experience. TortoiseGit has icon overlays though. The two work quite nicely together, so just install them both, use them for their strengths, and ignore them for their weaknesses.”]
Looking for one takes us here [https://github.com/gitextensions/gitextensions], here [https://github.com/gitextensions/gitextensions/releases/tag/v2.50.01]
and the other here [tortoisegit] and [https://tortoisegit.org/]
You will see from the last screenshot that it works well enough, imo.