Introduces the wcag2a/wcag2aa E2E suite from the test-suite branch with the color-contrast rule active — no disableRules exclusion. Also adds /coverage/ to .prettierignore so generated lcov reports don't fail the lint hook. This commit intentionally fails the axe suite until the contrast fixes land in the next commits. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>