Keep legacy Matrix dedupe retention private and preserve the tests independent 30-day expectation. Durable ingress continues to own live replay retention. Delete the superseded event fixture and register the documented presence benchmark entry.
Validated 62 Matrix tests, the shared retention case, targeted types/lint/format, and P2 review. All three deadcode scans ran; only the unrelated CopilotToolBridgeInput test type from #177267 remains.