## Problem When placeholder user reassignment fails, the UI shows a "Failed" badge with no way to retry. Users are stuck with no recovery path. Split from #589777 per [refinement notes](https://gitlab.com/gitlab-org/gitlab/-/work_items/589777#note_3148154749). #589777 covers the API; this issue covers the UI. ## Proposal Add a "Retry" button for `FAILED` status source users in the placeholder reassignment UI.