fix: use server-side time_ago for notification timestamps

views/layouts/main.php

@@ -295,7 +295,7 @@ function renderNotifications(items, unreadCount) {
             + '<div class="notif-content">'
             + '<div class="notif-title">' + escapeHtml(n.title) + '</div>'
             + '<div class="notif-message">' + escapeHtml(n.message) + '</div>'
-            + '<div class="notif-time">' + timeAgo(n.created_at) + '</div>'
+            + '<div class="notif-time">' + (n.time_ago || '') + '</div>'
             + '</div>'
             + (n.is_read ? '' : '<div class="notif-dot"></div>')
             + '</div>';
@@ -374,18 +374,6 @@ function escapeHtml(str) {
     return d.innerHTML;
 }
 
-function timeAgo(dateStr) {
-    const now = new Date();
-    const d = new Date(dateStr.replace(' ', 'T') + (dateStr.includes('Z') ? '' : 'Z'));
-    const diff = Math.floor((now - d) / 1000);
-    if (diff < 60) return 'just now';
-    if (diff < 3600) return Math.floor(diff / 60) + 'm ago';
-    if (diff < 86400) return Math.floor(diff / 3600) + 'h ago';
-    const days = Math.floor(diff / 86400);
-    if (days < 7) return days + 'd ago';
-    return d.toLocaleDateString();
-}
-
 // Poll unread count every 60s
 setInterval(updateUnreadCount, 60000);
 // Initial fetch