Add engine validation script with attack_coin_status effect handler
- Add attack_coin_status effect handler for coin-flip status conditions
(e.g., Thunder Shock paralysis on heads)
- Create comprehensive engine_validation.py script (~1250 lines) that
validates game engine behavior with 29 test cases:
- Illegal moves (attack without energy, wrong turn, evolution rules)
- Energy mechanics (attachment limits, cost validation)
- Weakness calculation (+20 additive mode)
- Status conditions (paralysis blocks actions, poison damage)
- Knockout flow (points, forced actions, state cleanup)
- Win conditions (4 points triggers game over)
- Update game_walkthrough.py Thunder Shock to use new effect handler
- Interactive prompts between sections (Enter to continue, q to quit)
- Uses seed=42 for deterministic, reproducible coin flips
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>