Accessibility is a coding standard, not a checklist

Enforces accessibility as a correctness property authored into each widget — Semantics(button/label) or ExcludeSemantics on every node, a11y state read from MediaQuery not app state, never MediaQuery.withClampedTextScaling / textScaleFactor / FittedBox / TextOverflow.ellipsis to fit a label, non-color redundant channels (icon+label+shape+text) for every state, contrast against composited backgrounds (4.5:1 body / 3:1 large), 44px single-tap targets, OrdinalSortKey traversal, and honoring boldText / reduce-motion. Use when adding a GestureDetector/InkWell or any tap target, adding an Icon or Image, reaching for withClampedTextScaling/FittedBox/ellipsis/textScaleFactor to m…