- Acknowledge start and end without waiting for persistence or dashboards.
- Keep runtime creation and finished-game removal on the response path.
- Serialize start, turn, and end bookkeeping per game in Quart tasks.
- Capture turn thinking before scheduling deferred persistence.
- Defer start metrics, logging, and stale-game pruning.
- Run legacy history exports in a worker thread.
- Record results and end metrics even when history export fails.
- Drain pending bookkeeping before closing storage during shutdown.
- Test sub-500 ms responses with slow backends and real SQLite.
- Cover event ordering, export failures, and rejected user agents.
