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PR state was written by two flows and the second one could not persist: the feedback fetch returned live PR data without saving it, and the browser patched its own store copy instead. Opening a PR's detail panel turned that tab purple while the kanban card and boot payload still read state=open, and a reload snapped it back. The backend is now the only writer — the feedback read reconciles through SyncTaskPR and publishes github.task_pr.updated, so every surface converges and the state survives a reload. SyncTaskPR also refuses to move a row out of merged, since GitHub cannot un-merge a PR.