Beyond Linting: Why We Switched To Semantic Contracts for A11y and Localization

I remember sitting in the war room three days before a major release. We were confident; our static accessibility (a11y) linter was passing, and our localization (l10n) unit tests, which performed simple string comparisons, returned green. Then, a beta user reported that the primary_submit_action button was physically impossible to tap because our localization file had grown the button label, pushing the touch target off-screen.