Similarly to [delayed deletion of projects by default](https://gitlab.com/gitlab-org/gitlab/-/issues/255449), we want to avoid accidental deletion of huge amount of valuable data. Instead of immediately deleting the group and all of its data, we switch to a 2 step process: 1. triggering group deletion only schedules the actual deletion at a later time 1. admin can opt for immediate deletion (UI only), but only after step `1` This process should be enabled for all new, top-level, premium+ groups on .com. Original proposal: https://gitlab.com/gitlab-org/gitlab/-/issues/241146 ## Proposal 1. introduce cascading namespace setting for `delayed_group_deletion` 1. add an instance-level setting for delayed group deletion (with default disabled) 1. enable the instance-level setting on .com