8f8fc98d6a
exportgraphics on headless invisible figures ignores XTickLabelRotation/ xtickangle, so the labels stayed horizontal. Draw the tick labels as rotated text objects (Rotation 90) instead, add bottom margin, and drop the 'training day' axis label below them. Regenerated all learning-curve figures. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>