Proof: Quote lifecycle retention now runs without blocking history-writer readiness, prevents concurrent maintenance passes, and bounds historical rollup catch-up before fail-closed pruning; regression tests cover the bounded stale-watermark path.
Assumptions: Forty-eight DB-backed rollup granularity windows per pass is sufficient to catch up historical backlog without returning the entire raw quote firehose in one query.
Still fake: Initial historical backlog may require multiple scheduled passes before pruning can begin; already-pruned non-success detail cannot be reconstructed.