Create a minimal backfill process to support transfering TLGs to Organizations for Artifact Registry support
## Problem statement
In order to support Artifact Registry customers, we need to automatically transfer a specific list of customer-owned Top-Level Groups (TLGs) into Organizations on gitlab.com.
This is a lightweight operation which creates a new Organization with the same name as the TLG, and updates the group reference to point this new Organization ID. The TLG's users should also be moved to the new Organization as members.
This makes no visible difference to customer experience or Organization usage alone – this comes later, as we selectively enable the feature and begin onboarding customers to Artifact Registry.
## DRI
@dblessing @rutgerwessels
## Exit criteria
* **Specific TLGs** on gitlab.com are associated with a non-default Organization ID
* **All users within these TLGs** are associated with a non-default Organization ID
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## Status 2026-04-30
Most of this work is being tracked in epic https://gitlab.com/groups/gitlab-org/-/work_items/21394. But I will update here for reporting purposes.
:clock1: **total hours spent this week by all contributors**: 25
:tada: **achievements**:
- https://gitlab.com/gitlab-org/gitlab/-/work_items/597580+ - Merged and deployed. We now have proper states that we need for the reconcilation/confirmation process.
- https://gitlab.com/gitlab-org/gitlab/-/work_items/597832+ remains ~"workflow::in dev"
:issue-blocked: **blockers**:
- None
:arrow_forward: **next**:
- https://gitlab.com/gitlab-org/gitlab/-/work_items/598469+
- https://gitlab.com/gitlab-org/gitlab/-/work_items/598074+
- https://gitlab.com/gitlab-org/gitlab/-/work_items/596669+
_Copied from https://gitlab.com/groups/gitlab-org/-/epics/21845#note_3301695593_
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epic