debug: Add comprehensive logging for toggle issue

Added debug logging to identify where enabled status is lost.

Backend Logging:
- Log what instance_settings["enabled"] value is read from DB
- Log the computed is_enabled boolean
- Log for both regular zones and Rest of World zone

Frontend Logging:
- Log all fetched zones data
- Log each method's enabled status
- Console output for easy debugging

This will show us:
1. What WooCommerce stores in DB
2. What backend reads from DB
3. What backend returns to frontend
4. What frontend receives
5. What frontend displays

Next: Check console + error logs to find the disconnect

admin-spa/src/routes/Settings/Shipping.tsx

@@ -38,7 +38,18 @@ export default function ShippingPage() {
   // Fetch shipping zones from WooCommerce
   const { data: zones = [], isLoading, refetch } = useQuery({
     queryKey: ['shipping-zones'],
-    queryFn: () => api.get('/settings/shipping/zones'),
+    queryFn: async () => {
+      const data = await api.get('/settings/shipping/zones');
+      console.log('[Shipping] Fetched zones:', data);
+      // Log each zone's methods
+      data.forEach((zone: any) => {
+        console.log(`[Shipping] Zone "${zone.name}" (ID: ${zone.id}):`, zone.rates);
+        zone.rates?.forEach((rate: any) => {
+          console.log(`  - ${rate.name}: enabled=${rate.enabled}`);
+        });
+      });
+      return data;
+    },
     staleTime: 5 * 60 * 1000, // 5 minutes
   });