Co-authored-by: Benjamin Koch <bbbsnowball@gmail.com>
This adds configuration flags that will match a user to pre-existing users
when logging in via OpenID Connect. This is useful when switching to
an existing SSO system.
Duplicating function signatures between server.py and server.pyi is
silly. This commit changes that by changing all `build_*` methods to
`get_*` methods and changing the `_make_dependency_method` to work work
as a descriptor that caches the produced value.
There are some changes in other files that were made to fix the typing
in server.py.
