fit_text always picks the largest ladder rung that fits its box. That's
right when an element owns dedicated space, but wrong when several
independently-fitted elements need to stay visually harmonious as the
panel grows: a score's box might have generous room while a neighboring
logo scales by a fixed geometry factor via px() — fit_text lets the score
balloon out of proportion (even overlapping the logo) even though its
individual pick is technically correct.
fit_text_proportional(text, box, base_size_px, ladder) instead targets
base_size_px * self.scale (the same scale factor px() already uses),
picking the nearest ladder rung at or below that target, still capped to
what fits the box, floored at the smallest rung when the target is below
every rung. Refactored the shared largest-that-fits/ellipsize walk into
_walk_ladder() so fit_text and fit_text_proportional don't duplicate it.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
