feat: @提及发送通知 + 通知点击定位高亮

- 新增 NotifyCommentMention 通知类型，归属 mention 分类 TAB
- parseMentions 中向被@用户发送通知（排除自己和重复通知）
- 消息中心 mention 通知可点击跳转至文章页面
- 通过 mention 通知进入时，来源评论置顶并持久半透明高亮
- 普通评论链接保持原有短暂高亮行为不变

templates/MetaLab-2026/static/js/post-comments.js

@@ -498,21 +498,45 @@
     }
 
     // ====== 评论高亮 ======
-    function highlightComment(commentId) {
+    function highlightComment(commentId, persistent) {
         var card = commentsList.querySelector('.comment-card[data-id="' + commentId + '"]') ||
                    commentsList.querySelector('.comment-reply-card[data-id="' + commentId + '"]');
         if (card) {
             commentsList.insertBefore(card, commentsList.firstChild);
             card.scrollIntoView({ behavior: 'smooth', block: 'start' });
-            card.style.background = '#fff8e1';
-            card.style.transition = 'background 1.5s';
-            setTimeout(function() { card.style.background = ''; }, 2000);
+            if (persistent) {
+                card.classList.add('highlight-mention');
+            } else {
+                card.style.background = '#fff8e1';
+                card.style.transition = 'background 1.5s';
+                setTimeout(function() { card.style.background = ''; }, 2000);
+            }
             return true;
         }
         return false;
     }
 
     var hash = window.location.hash;
+
+    // @提及通知进入：置顶 + 持久高亮
+    var mentionMatch = hash.match(/^#mention-(\d+)$/);
+    if (mentionMatch) {
+        var mentionCommentId = mentionMatch[1];
+        var mentionInterval = setInterval(function() {
+            if (highlightComment(mentionCommentId, true)) {
+                clearInterval(mentionInterval);
+            }
+        }, 300);
+        setTimeout(function() {
+            clearInterval(mentionInterval);
+            if (!commentsList.querySelector('.comment-card[data-id="' + mentionCommentId + '"]') &&
+                !commentsList.querySelector('.comment-reply-card[data-id="' + mentionCommentId + '"]')) {
+                showToast('该评论已不存在');
+            }
+        }, 3000);
+    }
+
+    // 普通评论/回复链接：短暂高亮
     var commentMatch = hash.match(/^#comment-(\d+)$/);
     if (commentMatch) {
         var targetCommentId = commentMatch[1];