WDYT, @cmd-johnson?

I'm not quite sure tbh
The defaults property holds data that can be overridden in each request, while the other properties are basically constant between all requests. I feel like promoting e.g. scope to the top level could suggest that that's what's used at all times, while nesting it into defaults makes it obvious that it's just... the default 😅

Not that it would make much of a difference in practice, though 🤷
Anyway, seeing as this would be a breaking change, I'd rather hold off on merging this just yet until the OIDC client (#39) is done