更新 index.html 模板，讓報名圖片變為可點擊連結

- 將個人報名和團體報名圖片加上超連結功能
- 連結會在新視窗開啟並具備安全屬性

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

Co-Authored-By: Claude <[email protected]>

templates/index.html

@@ -1477,7 +1477,7 @@
                                             </div>
                                             <div>
                                                 <label class="block text-sm font-medium text-gray-700 mb-1">學校報名連結</label>
-                                                <input type="url" id="var-schoolRegUrl" value="https://www.facebook.com/CoWrite30" class="w-full px-4 py-2 border rounded-lg focus:ring-2 focus:ring-green-500 focus:border-transparent">
+                                                <input type="url" id="var-schoolRegUrl" value="https://forms.gle/zuwHQSdAtv6EVKWLA" class="w-full px-4 py-2 border rounded-lg focus:ring-2 focus:ring-green-500 focus:border-transparent">
                                             </div>
                                         </div>
                                     </div>