Goal

Create a branch/draft PR in the inventory-api repository with code from relations-api taken over and merged into the inventory service. The code on this branch should be mergeable, fully tested and ready to deploy to stage and production.

Decisions taken for this PR should be informed by KSL-38: Merging Inventory API and Relations API and the top level feature.

Such a PR was created for discussion purposes as part of RHCLOUD-43569. It was close-to-mergeable at that time. It may make sense – assuming that inventory-api has not changed substantially in the meantime – to rebase this PR or to have AI follow the same plan to produce a new PR. The plan can be taken from the README of that PR.

Considerations

1. The timing of this work should align with the overall plan. (See RHCLOUD-45309.)
2. We don't want to have a long running PR, so ideally this work should be undertaken when we are reasonably confident that we can move to operational deployment pretty much straight away.
3. As per the plan, and the original PR, above, we need to ensure that good regression testing is in place and brought over from relations where needed.

Definition of done

A mergeable PR for inventory-api, bringing in relations-api code, and making necessary refactoring changes, is produced and can be merged within a reasonably short timescale.