feat(voice-recognition): add speech recognition and emotion-based video switching

Implement voice recognition functionality that displays transcript in a styled container. Add emotion analysis to switch videos based on detected positive/negative keywords in speech. Includes UI updates for transcript display and microphone interaction.

index.html

@@ -38,6 +38,11 @@
             </div>
         </header>
 
+        <!-- 语音识别结果显示区域 -->
+        <div class="transcript-container">
+            <p id="transcript"></p>
+        </div>
+
         <!-- 底部麦克风和链接 -->
         <footer class="bottom-bar">
             <button class="mic-button" id="mic-button" aria-label="Start Listening">