Modeling craft
- Leak-safe target encoding computed inside each CV fold so a player's own outcome never leaks into their features.
- Missingness-as-signal design: per-drill missing flags, drills-missing counts, and full-combine indicators.
- Two complementary models on purpose - LightGBM on encoded schools, CatBoost on raw categoricals - blended 85/15 by OOF AUC.
- Variance control on a 696-row test set via 3-seed x 5-fold averaging, trusting OOF AUC over the noisy public leaderboard.