AuthToken for M$ graphapi

This is a one to one translation of the python code i use for the same purpose. Why golang? No benefits other than that learning a new programming lanugage is never wrong, and golang is kinda cool.

I've looked at several examples and I think that this is now a package.. more or less.

I need to write tests.. or let copilot write them for me.

Then I need to write an app.. that does something - using this as a package.

Interesting times ahead!