Covers: game-lifecycle DB fixes (stranded active games, populated
metadata, winner_id, stats idempotency) and staging leaderboard
include-test override.
Also aligns FastAPI app version in server/main.py (was stuck at 3.2.0)
with the actual release.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>