feat: 統一所有選擇題組件的選項布局和圖片功能

## 主要改動

### 響應式選項布局統一
- VocabChoiceTest: 改為2x2網格布局，支援響應式設計
- VocabListeningTest: 添加響應式斷點 (grid-cols-1 sm:grid-cols-2)
- SentenceListeningTest: 改為響應式2x2網格，移除選項標籤

### 圖片功能完善
- SentenceListeningTest: 新增exampleImage和onImageClick支援
- 添加完整的圖片顯示區塊和點擊處理
- review-design頁面: 為SentenceListeningTest傳遞圖片屬性

### 視覺一致性提升
- 所有選擇題組件採用相同的按鈕樣式和網格布局
- 統一文字置中對齊和font-medium字重
- 手機版自動切換為單列布局，提升觸控體驗
- 桌面版使用2x2網格，充分利用屏幕空間

### 響應式設計
- 小屏幕 (< 640px): 選項垂直單列排列
- 中等以上屏幕 (≥ 640px): 選項2x2網格排列
- 保持所有組件一致的響應式行為

🤖 Generated with [Claude Code](https://claude.ai/code)

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

frontend/app/review-design/page.tsx

@@ -231,8 +231,10 @@ export default function ReviewTestsPage() {
                 exampleTranslation={mockCardData.exampleTranslation}
                 difficultyLevel={mockCardData.difficultyLevel}
                 options={vocabChoiceOptions}
+                exampleImage={mockCardData.exampleImage}
                 onAnswer={handleAnswer}
                 onReportError={handleReportError}
+                onImageClick={handleImageClick}
               />
             )}
 

frontend/components/review/review-tests/SentenceListeningTest.tsx

@@ -7,8 +7,10 @@ interface SentenceListeningTestProps {
   exampleTranslation: string
   difficultyLevel: string
   options: string[]
+  exampleImage?: string
   onAnswer: (answer: string) => void
   onReportError: () => void
+  onImageClick?: (image: string) => void
   disabled?: boolean
 }
 
@@ -18,8 +20,10 @@ export const SentenceListeningTest: React.FC<SentenceListeningTestProps> = ({
   exampleTranslation,
   difficultyLevel,
   options,
+  exampleImage,
   onAnswer,
   onReportError,
+  onImageClick,
   disabled = false
 }) => {
   const [selectedAnswer, setSelectedAnswer] = useState<string | null>(null)
@@ -70,14 +74,29 @@ export const SentenceListeningTest: React.FC<SentenceListeningTestProps> = ({
           </div>
         </div>
 
-        {/* 選項區域 - 垂直列表布局 */}
-        <div className="grid grid-cols-1 gap-3 mb-6">
+        {/* 圖片區（如果有） */}
+        {exampleImage && (
+          <div className="mb-6">
+            <div className="bg-gray-50 rounded-lg p-4">
+              <h3 className="font-semibold text-gray-900 mb-2 text-left">圖片提示</h3>
+              <img
+                src={exampleImage}
+                alt="Example illustration"
+                className="w-full max-w-md mx-auto rounded-lg cursor-pointer"
+                onClick={() => onImageClick?.(exampleImage)}
+              />
+            </div>
+          </div>
+        )}
+
+        {/* 選項區域 - 響應式網格布局 */}
+        <div className="grid grid-cols-1 sm:grid-cols-2 gap-3 mb-6">
           {options.map((sentence, idx) => (
             <button
               key={idx}
               onClick={() => handleAnswerSelect(sentence)}
               disabled={disabled || showResult}
-              className={`w-full p-4 text-left rounded-lg border-2 transition-all ${
+              className={`p-4 text-center rounded-lg border-2 transition-all ${
                 showResult
                   ? sentence === example
                     ? 'border-green-500 bg-green-50 text-green-700'
@@ -87,8 +106,7 @@ export const SentenceListeningTest: React.FC<SentenceListeningTestProps> = ({
                   : 'border-gray-200 hover:border-blue-300 hover:bg-blue-50'
               }`}
             >
-              <div className="text-sm text-gray-600 mb-1">選項 {String.fromCharCode(65 + idx)}:</div>
-              <div className="text-base">{sentence}</div>
+              <div className="text-lg font-medium">{sentence}</div>
             </button>
           ))}
         </div>

frontend/components/review/review-tests/VocabChoiceTest.tsx

@@ -72,14 +72,14 @@ export const VocabChoiceTest: React.FC<VocabChoiceTestProps> = ({
           </div>
         </div>
 
-        {/* 選項區域 */}
-        <div className="space-y-3 mb-6">
+        {/* 選項區域 - 響應式網格布局 */}
+        <div className="grid grid-cols-1 sm:grid-cols-2 gap-3 mb-6">
           {options.map((option, idx) => (
             <button
               key={idx}
               onClick={() => handleAnswerSelect(option)}
               disabled={disabled || showResult}
-              className={`w-full p-4 text-left rounded-lg border-2 transition-all ${
+              className={`p-4 text-center rounded-lg border-2 transition-all ${
                 showResult
                   ? option === word
                     ? 'border-green-500 bg-green-50 text-green-700'
@@ -89,7 +89,7 @@ export const VocabChoiceTest: React.FC<VocabChoiceTestProps> = ({
                   : 'border-gray-200 hover:border-blue-300 hover:bg-blue-50'
               }`}
             >
-              {option}
+              <div className="text-lg font-medium">{option}</div>
             </button>
           ))}
         </div>

frontend/components/review/review-tests/VocabListeningTest.tsx

@@ -72,7 +72,7 @@ export const VocabListeningTest: React.FC<VocabListeningTestProps> = ({
         </div>
 
         {/* 選項區域 - 2x2網格布局 */}
-        <div className="grid grid-cols-2 gap-3 mb-6">
+        <div className="grid grid-cols-1 sm:grid-cols-2 gap-3 mb-6">
           {options.map((option) => (
             <button
               key={option}