feat: 会员中心全局页面跳转过渡动画

header.php: CSS 入场动画(fadeIn + translateY)
footer.php: JS 拦截链接点击，先淡出再跳转
- 入场: 0.35s 从下方8px渐显
- 离场: 0.25s 向上8px渐隐
- 跳过: 锚点/javascript:/新窗口/修饰键

clientarea/hgcloud/header.php

@@ -17,6 +17,24 @@
     <!-- 模板样式 -->
     <link rel="stylesheet" href="/{$template_catalog}/template/{$public_themes}/css/common/reset.css">
 
+    <!-- 页面过渡动画 -->
+    <style>
+      body {
+        animation: pageEnter 0.35s ease both;
+      }
+      body.page-leaving {
+        animation: pageLeave 0.25s ease both;
+      }
+      @keyframes pageEnter {
+        from { opacity: 0; transform: translateY(8px); }
+        to   { opacity: 1; transform: translateY(0); }
+      }
+      @keyframes pageLeave {
+        from { opacity: 1; transform: translateY(0); }
+        to   { opacity: 0; transform: translateY(-8px); }
+      }
+    </style>
+
     <script src="/{$template_catalog}/template/{$themes}/theme/index.js"></script>
 
     <link rel="stylesheet" href="/{$template_catalog}/template/{$public_themes}/css/common/common.css">