feat(coverpage): 更新下载页面的 Mac 版本选择功能

- 将原有的 Mac 下载链接替换为下拉菜单选项
- 添加了针对 Intel 芯片和 Apple 芯片的不同版本下载链接
- 重新组织了按钮区域的 HTML 结构
- 保留了 Windows 版本的直接下载功能
- 使用注释包裹旧代码以便后续参考

_coverpage.md

@@ -72,10 +72,21 @@
     <video class="screen-video" autoplay loop muted playsinline>
       <source src="./_media/video/sky.mp4" type="video/mp4">
     </video>
-    <div class="buttons">
+    <!-- <div class="buttons">
       <a href="./_media/package/win-luckday-sky.zip" rel="noopener" target="_blank"><span>Win 下载</span>
       </a>
       <a href="./_media/package/mac-luckday-sky.zip" rel="noopener" target="_blank"><span>Mac 下载</span></a>
+    </div> -->
+    <div class="buttons">
+      <a href="./_media/package/win-luckday-sky.zip" rel="noopener" target="_blank"><span>Win 下载</span>
+      </a>
+      <div class="dropdown">
+        <a class="dropdown-toggle" href="javascript:void(0)"><span>Mac 下载</span></a>
+        <div class="dropdown-menu">
+          <a href="./_media/package/mac-x64-luckday-sky.zip" rel="noopener" target="_blank" style="width: 100%"><span>Mac (Intel 芯片)</span></a>
+          <a href="./_media/package/mac-arm64-luckday-sky.zip" rel="noopener" target="_blank" style="width: 100%"><span>Mac (Apple 芯片)</span></a>
+        </div>
+      </div>
     </div>
   </div>
 </div>