공정성 확인: 결과 화면에서 브라우저가 SHA-256(씨앗)을 직접 계산해 시작 때 공개한 값과 비교

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

e2e/omok.e2e.ts

@@ -129,6 +129,10 @@ try {
     await a.getByText('🎉 이겼어요!').waitFor();
     await b.getByText('아쉽게 졌어요').waitFor();
     await a.waitForTimeout(500); // let the sheet animation finish
+    // Fairness check: the browser recomputes SHA-256(seed) and compares with the published hash.
+    await a.getByText('공정성 확인').click();
+    await a.getByRole('button', { name: '내 브라우저에서 직접 확인하기' }).click();
+    await a.getByText('✓ 일치해요').waitFor();
     await a.screenshot({ path: join(SHOTS, '3-result-pc.png') });
     await b.screenshot({ path: join(SHOTS, '4-result-phone.png') });
   });