api/vault: Re-add obj_type and obj_id to legacy API endpoints
This broke Guix's client implementation: https://lists.gnu.org/archive/html/guix-devel/2021-09/msg00115.html
Migrated from D6222 (view on Phabricator)
This broke Guix's client implementation: https://lists.gnu.org/archive/html/guix-devel/2021-09/msg00115.html
Migrated from D6222 (view on Phabricator)