- Add roundtrip tests for all PlayerAction variants (Hoshe #6) - Add roundtrip tests for all EntityKind variants (Hoshe #6) - Add day wraparound at midnight edge case test (Hoshe #7) - Add day() calculation test (Hoshe #7) - Add out-of-order input rejection test (Hoshe #7) - Total: 15 → 20 tests Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>