Fix error monitoring date filter

src/pages/admin/ErrorMonitoring.tsx

@@ -12,6 +12,20 @@ import { ErrorDetailsModal } from '@/components/admin/ErrorDetailsModal';
 import { ErrorAnalytics } from '@/components/admin/ErrorAnalytics';
 import { format } from 'date-fns';
 
+// Helper to calculate date threshold for filtering
+const getDateThreshold = (range: '1h' | '24h' | '7d' | '30d'): string => {
+  const now = new Date();
+  const msMap = {
+    '1h': 60 * 60 * 1000,           // 1 hour in milliseconds
+    '24h': 24 * 60 * 60 * 1000,     // 1 day
+    '7d': 7 * 24 * 60 * 60 * 1000,  // 7 days
+    '30d': 30 * 24 * 60 * 60 * 1000, // 30 days
+  };
+  
+  const threshold = new Date(now.getTime() - msMap[range]);
+  return threshold.toISOString();
+};
+
 export default function ErrorMonitoring() {
   const [selectedError, setSelectedError] = useState<any>(null);
   const [searchTerm, setSearchTerm] = useState('');
@@ -22,13 +36,6 @@ export default function ErrorMonitoring() {
   const { data: errors, isLoading, refetch } = useQuery({
     queryKey: ['admin-errors', dateRange, errorTypeFilter, searchTerm],
     queryFn: async () => {
-      const dateMap = {
-        '1h': '1 hour',
-        '24h': '1 day',
-        '7d': '7 days',
-        '30d': '30 days',
-      };
-
       let query = supabase
         .from('request_metadata')
         .select(`
@@ -42,7 +49,7 @@ export default function ErrorMonitoring() {
           )
         `)
         .not('error_type', 'is', null)
-        .gte('created_at', `now() - interval '${dateMap[dateRange]}'`)
+        .gte('created_at', getDateThreshold(dateRange))
         .order('created_at', { ascending: false })
         .limit(100);