fix: dual-layer persistence (Backend JSON + LocalStorage Backup) to survive environment restarts

frontend/app/page.tsx

@@ -118,7 +118,11 @@ export default function HomePage() {
       }
 
       try {
-        const history = await fetchAnalysisHistory();
+        let history = await fetchAnalysisHistory();
+        if (history.length === 0) {
+          const localHistory = localStorage.getItem('andes_analysis_history_backup');
+          if (localHistory) history = JSON.parse(localHistory);
+        }
         setAnalysisHistory(history);
       } catch (e) {
         console.error("History load error", e);
@@ -126,7 +130,11 @@ export default function HomePage() {
 
       try {
         const { fetchSearchHistory } = await import("../lib/api");
-        const sHistory = await fetchSearchHistory();
+        let sHistory = await fetchSearchHistory();
+        if (sHistory.length === 0) {
+          const localSearch = localStorage.getItem('andes_search_history_backup');
+          if (localSearch) sHistory = JSON.parse(localSearch);
+        }
         setSearchHistory(sHistory);
       } catch (e) {
         console.error("Search history load error", e);
@@ -143,6 +151,19 @@ export default function HomePage() {
     init();
   }, []);
 
+  // Backup history to localStorage to survive HF Space restarts
+  useEffect(() => {
+    if (analysisHistory.length > 0) {
+      localStorage.setItem('andes_analysis_history_backup', JSON.stringify(analysisHistory));
+    }
+  }, [analysisHistory]);
+
+  useEffect(() => {
+    if (searchHistory.length > 0) {
+      localStorage.setItem('andes_search_history_backup', JSON.stringify(searchHistory));
+    }
+  }, [searchHistory]);
+
   const handleTenderSelect = (tender: Tender) => {
     setSelectedTender(tender);
     setActiveTab("Agent Analysis");