XGB: query was selecting features from ml_all_scores which doesn't
store them. Now joins ml_all_scores (labels) with view_ai_features_1h
(features). Dynamically discovers available columns to skip thesis §5
features not present in the view. Returns (model, features) tuple.
SHAP: TreeExplainer doesn't support isotree. Fall back to permutation-
based Explainer(model.decision_function, X_sample) for isotree.
Verified: XGB trained on 50000 labels (18436 positives), triple-voice
ensemble scoring active (EIF+AE+XGB), SHAP silent.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>