Thanks, @mishav, @Kfawcett, @NigelG, and @romanmg for the tips. I kind of figured I would have to basically self-handle this particular auth. And I do have it to the stage where I am successfully retrieving the authorization code and exchanging it for / retrieving the first set of access and refresh tokens.
What I find, however, is that the one downfall of this in Bubble is that it becomes difficult to set up further calls in the API connector as the “Initialize Call” step gets a bit tricky. I’ve not gotten this down to a science yet…
At any rate, in addition to the very good post that @Kfawcett points to, there is this helpful post and quite clear sample project that helped me get the this point:
I think I’m still doing something derpy with the required Authorization header for this particular API, but it was getting late.
Once I have this working very slickly and smoothly, the setup and management of self-handled “user is offline” access is something I’ll create a video about. Feels to me like Bubble makes this all just a little bit harder than it potentially needs to be.