rather than roles, matching tokens
because oauth clients are mostly involved with issuing tokens,
they don't have roles themselves (their owners do).
This deprecates the `oauth_roles` config on Spawners and Services, in favor of `oauth_allowed_scopes`.
The ambiguously named `oauth_scopes` is renamed to `oauth_access_scopes`.
tokens have scopes
instead of roles, which allow tokens to change permissions over time
This is mostly a low-level change,
with little outward-facing effects.
- on upgrade, evaluate all token role assignments to their current scopes,
and store those scopes on the tokens
- assigning roles to tokens still works, but scopes are evaluated and validated immediately,
rather than lazily stored as roles
- no longer need to check for role permission changes on startup, because token permissions aren't affected
- move a few scope utilities from roles to scopes
- oauth allows specifying scopes, not just roles.
But these are still at the level specified in roles,
not fully-resolved scopes.
- more granular APIs for working with scopes and roles
Still to do later:
- expose scopes config for Spawner/service
- compute 'full' intersection of requested scopes, rather than on the 'raw' scope list in roles
- move spec to _static/rest-api.yml, since the original yaml must be served
- copy javascript rendering code from FastAPI (uses swagger-ui)
- remove link to pet store, since there isn't a big enough difference to duplicate it
- remove bootprint rendering with node
