This adds an initial "/.well-known/openid-configuration" service
discovery endpoint for use by OpenID Connect clients.
Signed-off-by: Michael Mayer <michael@photoprism.app>
This commit also adds an /api/v1/oauth/logout endpoint that allows
clients to delete their sessions (access tokens) as needed.
Signed-off-by: Michael Mayer <michael@photoprism.app>