Fix vendor and category page loading issues

inventory-server/src/routes/vendors.js

@@ -84,16 +84,28 @@ router.get('/', async (req, res) => {
       SELECT 
         COUNT(DISTINCT p.vendor) as totalVendors,
         COUNT(DISTINCT CASE WHEN vm.status = 'active' THEN p.vendor END) as activeVendors,
-        AVG(vm.avg_lead_time_days) as avgLeadTime,
-        AVG(vm.order_fill_rate) as avgFillRate,
-        AVG(vm.on_time_delivery_rate) as avgOnTimeDelivery
+        COALESCE(ROUND(AVG(NULLIF(vm.avg_lead_time_days, 0)), 1), 0) as avgLeadTime,
+        COALESCE(ROUND(AVG(NULLIF(vm.order_fill_rate, 0)), 1), 0) as avgFillRate,
+        COALESCE(ROUND(AVG(NULLIF(vm.on_time_delivery_rate, 0)), 1), 0) as avgOnTimeDelivery
       FROM products p
       LEFT JOIN vendor_metrics vm ON p.vendor = vm.vendor
     `);
 
     res.json({
-      vendors,
-      stats: stats[0],
+      vendors: vendors.map(vendor => ({
+        ...vendor,
+        avg_lead_time_days: parseFloat(vendor.avg_lead_time_days || 0),
+        on_time_delivery_rate: parseFloat(vendor.on_time_delivery_rate || 0),
+        order_fill_rate: parseFloat(vendor.order_fill_rate || 0),
+        total_orders: parseInt(vendor.total_orders || 0),
+        active_products: parseInt(vendor.active_products || 0)
+      })),
+      stats: {
+        ...stats[0],
+        avgLeadTime: parseFloat(stats[0].avgLeadTime || 0),
+        avgFillRate: parseFloat(stats[0].avgFillRate || 0),
+        avgOnTimeDelivery: parseFloat(stats[0].avgOnTimeDelivery || 0)
+      },
       pagination: {
         total: countResult[0].total,
         pages: Math.ceil(countResult[0].total / limit),