feat(SW-497): added link and refs to site config

lib/graphql/Query/SiteConfig.graphql

@@ -1,3 +1,5 @@
+#import "../Fragments/System.graphql"
+
 #import "../Fragments/Alert.graphql"
 
 query GetSiteConfig($locale: String!) {
@@ -16,3 +18,22 @@ query GetSiteConfig($locale: String!) {
     }
   }
 }
+
+query GetSiteConfigRef($locale: String!) {
+  all_site_config(limit: 1, locale: $locale) {
+    items {
+      sitewide_alert {
+        alertConnection {
+          edges {
+            node {
+              ...AlertRef
+            }
+          }
+        }
+      }
+      system {
+        ...System
+      }
+    }
+  }
+}