Add production, production-prepared, production-parallel and
production-busy modes plus an optional 1..512 round count. Repeated
rounds validate against a round-scaled CPU double reference and report
per-round throughput; production-parallel exercises concurrent
prepared-chunk submission and production-busy adds host spin workers to
probe contention.
Add a bounded per-chunk center-tile selector to the real-event replay prototype and retain the paired timing, mixed-boundary, CPU, HIP, and sandbox-failure evidence.
Capture prepared events through a test-only producer consumer and measure serial and indexed parallel generation independently. Compare the production atomic kernel with bounded pixel-owned tile reductions while preserving double HDR, cache support, and direct fallback ordering.
Validate captured inputs, edge and multichunk fixtures, CPU/HIP renderer regressions, and 45 isolated final replays. Keep the production HIP algorithm unchanged because gains depend on event distribution.
wyj