Update VoltageHeatmap.tsx

Author: SaniyaKalamkar

frontend/src/VoltageHeatmap.tsx

@@ -29,7 +29,7 @@ export default function VoltageHeatmap({ voltages, loading = false, label, dataC
   const fetchHeatmap = async (v: number[], dcBus?: number | null) => {
     setFetching(true); setError(null);
       const HF_SPACE_URL = "https://gpu2grid-live.hf.space";
-      
+      try {
       const res = await fetch(`${HF_SPACE_URL}/api/heatmap`, {
         method: "POST",
         headers: { "Content-Type": "application/json" },