Function repair 

pub fn repair(colors: &mut Colors) -> Vec<ContrastFinding>

Step every foreground that misses a floor out, in OKLCH lightness at its own hue and chroma, until it holds. Grounds never move: the ladder is the theme’s, and a foreground that cannot reach its floor on one ground without losing another (an ink tier on a ladder that straddles it) ends at the extreme that serves the hardest ground. Returns what was missed before the repair.