feat(e2e): add axe-core accessibility fixture

e2e/fixtures.ts

@@ -0,0 +1,12 @@
+import { test as base, expect } from "@playwright/test";
+import AxeBuilder from "@axe-core/playwright";
+
+export const test = base.extend<{ axeCheck: void }>({
+  axeCheck: [async ({ page }, use) => {
+    await use();
+    const results = await new AxeBuilder({ page }).analyze();
+    expect(results.violations).toEqual([]);
+  }, { auto: true }],
+});
+
+export { expect } from "@playwright/test";