Pokémon TCG — BC Large Model Submission Pipeline

Submit a BC (behavioral cloning) Transformer agent for the Pokémon TCG AI Battle competition. Validated 2026-07-30: best.pth (15-epoch BC Large, d_model=256) → **public LB 600.0** (vs prior 165.6 — 3.6× improvement from using the best checkpoint instead of a stale submission). Use when: (1) training a BC agent on Kaggle Pokémon TCG episodes, (2) submitting a tar.gz agent for the competition, (3) scaling BC data to 80K+ games. Critical pitfall: your highest validation WR checkpoint is almost certainly NOT what you last saved to your submission directory — always verify the submission's model_bc.pth matches the best checkpoint before submitting. Stream-sampling (load 50K pe…