fix uptime on dashboard

webui/src/pages/Dashboard.jsx

@@ -62,6 +62,23 @@ function Dashboard({ isOnline }) {
     }
   };
 
+  const formatUptime = (seconds) => {
+    if (!seconds || seconds < 0) return '0s';
+    
+    const days = Math.floor(seconds / 86400);
+    const hours = Math.floor((seconds % 86400) / 3600);
+    const minutes = Math.floor((seconds % 3600) / 60);
+    const secs = Math.floor(seconds % 60);
+    
+    const parts = [];
+    if (days > 0) parts.push(`${days}d`);
+    if (hours > 0) parts.push(`${hours}h`);
+    if (minutes > 0) parts.push(`${minutes}m`);
+    if (secs > 0 || parts.length === 0) parts.push(`${secs}s`);
+    
+    return parts.join(' ');
+  };
+
   const handleServiceControl = async (serviceName, action) => {
     if (!isOnline) return;
     
@@ -224,7 +241,7 @@ function Dashboard({ isOnline }) {
                 <div className="ml-4">
                   <p className="text-sm font-medium text-gray-500">Uptime</p>
                   <p className="text-lg font-semibold text-gray-900">
-                    {Math.floor((cellStatus.uptime || 0) / 3600)}h {Math.floor(((cellStatus.uptime || 0) % 3600) / 60)}m
+                    {formatUptime(cellStatus.uptime || 0)}
                   </p>
                 </div>
               </div>