feat: add retake attempt functionality and update translations for retake button

frontend/src/components/Landing.tsx

@@ -11,6 +11,7 @@ interface Props {
   onResume: () => void
   onClearHistory: () => void
   onReviewAttempt: (entry: HistoryEntry) => void
+  onRetakeAttempt?: (entry: HistoryEntry) => void
 }
 
 const SAMPLES = [
@@ -19,7 +20,7 @@ const SAMPLES = [
   { path: '/samples/mixed-demo.json', title: 'Mixed Demo — Every Question Type', meta: '4 questions · Untimed · Media', mark: '◇' },
 ]
 
-export default function Landing({ onLoadExam, history, onResume, onClearHistory, onReviewAttempt }: Readonly<Props>) {
+export default function Landing({ onLoadExam, history, onResume, onClearHistory, onReviewAttempt, onRetakeAttempt }: Readonly<Props>) {
   const { t } = useTranslation()
   const [err, setErr] = useState<string | null>(null)
   const [dragOver, setDragOver] = useState(false)
@@ -483,6 +484,9 @@ Set a 20-minute time limit. Include explanations for each answer."
                 </div>
                 <div className="mono muted" style={{ fontSize: 12 }}>{formatTime(h.elapsedMs)}</div>
                 <div className={`score-pill ${passed ? 'pass' : 'fail'}`}>{pct}%</div>
+                {onRetakeAttempt && (
+                  <button className="btn btn-ghost btn-sm" onClick={() => onRetakeAttempt(h)}>{t('landing.retake')}</button>
+                )}
                 <button className="btn btn-ghost btn-sm" onClick={() => onReviewAttempt(h)}>{t('landing.review')}</button>
               </div>
             )