docs: added reference for JS Client (#1629)

* added reference for JS Client

* added reference for JS Client

* added reference for JS Client

www/docs/docusaurus.config.js

@@ -68,6 +68,11 @@ module.exports = {
           sidebarId: "servicesSidebar",
           label: "Services Reference",
         },
+        {
+          type: "docSidebar",
+          sidebarId: "jsClientSidebar",
+          label: "JS Client Reference",
+        },
         {
           href: `https://docs.medusajs.com/api/store`,
           target: "_self",