Now that panels frost at full alpha, the slider's old top end (multiplier 4.0)
was far too blurry. Cap the range at multiplier 1.25 (kAcrylicMaxBlur) — the
slider still reads 0–100%, but 100% now maps to a moderate frost instead of a
heavy wash. Snap-to-off threshold scales with the new range, and a value saved
under the old 0–4 range is clamped on load so it lands within 0–100%.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>