Configures Lighthouse CI's Accessibility category for automated accessibility testing (a11y / WCAG coverage) - `categories:accessibility` audits backed by axe-core (axe) - with per-URL minimum-score assertions (fail a build when a page's score drops below a threshold) and per-audit overrides, distinct from the Performance category that `lighthouse-perf` covers. Use when the project already runs Lighthouse CI for Web Vitals and the team wants to add accessibility coverage in the same pipeline rather than spinning up a separate scanner.