fix: resolve triplicated ASIN in Forecast View and improve metadata mapping

App.tsx

@@ -90,7 +90,7 @@ const App: React.FC = () => {
       console.log('[App] Successfully loaded', data.length, 'rows');
 
       // Refresh forecast too
-      handleForecastFetch(data, globalAsinMetadata);
+      handleForecastFetch(data);
     } catch (error) {
       console.error("Failed to fetch/parse CSV", error);
       alert("Error loading data. Please refresh the page.");
@@ -143,7 +143,7 @@ const App: React.FC = () => {
     }
   }, []);
 
-  const handleForecastFetch = useCallback(async (sales: SalesRecord[], meta: Map<string, { sku: string; title: string; line: string }>) => {
+  const handleForecastFetch = useCallback(async (sales: SalesRecord[]) => {
     try {
       console.log('[App] Fetching forecast from /forecast.xlsx...');
       const response = await fetch('/forecast.xlsx');
@@ -151,6 +151,17 @@ const App: React.FC = () => {
 
       const buffer = await response.arrayBuffer();
       const fcRecords = await processForecastExcel(buffer);
+
+      // Build precise metadata map from sales records
+      const meta = new Map<string, { sku: string; title: string; line: string }>();
+      sales.forEach(r => {
+        const asin = r.asin.trim().toUpperCase();
+        const existing = meta.get(asin);
+        if (!existing || (r.title && r.title.length > (existing.title?.length || 0))) {
+          meta.set(asin, { sku: r.sku, title: r.title, line: r.line });
+        }
+      });
+
       const viewData = calculateForecastViewData(sales, fcRecords, meta);
       setForecastData(viewData);
       console.log('[App] Forecast loaded:', viewData.length, 'records');
@@ -234,7 +245,7 @@ const App: React.FC = () => {
       handleTrafficFetch();
 
       // 1d. Fetch Forecast data
-      handleForecastFetch(cachedData || [], globalAsinMetadata);
+      handleForecastFetch(cachedData || []);
     };
     initApp();
   }, [handleDataFetch]);