Add /version endpoint

[rod-glover]

It would be helpful to be able to verify definitively the version of the backend that is actually responding.

[corviday]

Would this make sense as part of the /health endpoint? I guess currently that endpoint takes a while to run, /version might make more sense as a standalone thing.

[rod-glover]

Given what you said, and on the principle of separation of concerns, separate makes sense.