Seven pre-implementation test cases covering: 108-sum invariant
preservation under profile-based boosts, D20 probability shift
magnitude at T4, pipeline collision risk between T4 rarity upgrade
and live-series post_player_updates, HoF rarity cap (non-contiguous
ID ladder), RP T1 achievability, SP/RP/batter T4 parity, and the
cross-season stat accumulation design decision that must be confirmed
before Phase 2 code is written.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
