Why: bind the task validation checkpoint to the latest integration baseline. Evidence: SELF recursive component checks; sync_base=2229d718c7b25941cba1c2464ddd62f9d7466bec; candidate=861f0099ddc52dcc90e5b048b7d69c4facd92f10. Impact: task metadata only. Refs: .task/feature-collab-storage-u6-events.md