appauth: Add token and user (with roles) to context

When successfully authenticating a user via apptoken, resolve the user's
roles and add the user and the token returned by the auth service to the
request context. Rely on the account_resolve middleware to add the reva
token to the outgoing request as the other auth middlewares do.

services/proxy/pkg/command/server.go

@@ -294,6 +294,7 @@ func loadMiddlewares(logger log.Logger, cfg *config.Config,
 		authenticators = append(authenticators, middleware.AppAuthAuthenticator{
 			Logger:              logger,
 			RevaGatewaySelector: gatewaySelector,
+			UserRoleAssigner:    roleAssigner,
 		})
 	}
 	authenticators = append(authenticators, middleware.NewOIDCAuthenticator(