Fix timestamp handling and improve data extraction in HistoryCharts component

frontend/src/components/HistoryCharts.jsx

@@ -57,25 +57,29 @@ const HistoryChartsContent = () => {
   data?.forEach(sensor => {
     if (sensor.value != null && grouped[sensor.valueType]) {
       grouped[sensor.valueType].push({
-        timestamp: new Date(sensor.timestamp),
+        timestamp: sensor.timestamp * 1000,
         value: sensor.value
       });
+
     }
   });
 
   const sortAndExtract = (entries) => {
     const sorted = entries.sort((a, b) => a.timestamp - b.timestamp);
+
     const labels = sorted.map(e =>
-      new Date(e.timestamp * 1000).toLocaleTimeString('es-ES', {
-        timeZone: 'Europe/Madrid',
+      new Date(e.timestamp).toLocaleTimeString('es-ES', {
+        timeZone: 'UTC',
         hour: '2-digit',
         minute: '2-digit'
       })
     );
+
 const values = sorted.map(e => e.value);
 return { labels, values };
   };
 
+
 const temp = sortAndExtract(grouped.temperature);
 const hum = sortAndExtract(grouped.humidity);
 const press = sortAndExtract(grouped.pressure);