docs: add a section on shipping options and requirement + improvements (#12990)

www/apps/resources/generated/generated-tools-sidebar.mjs

@@ -819,6 +819,14 @@ const generatedgeneratedToolsSidebarSidebar = {
                   "path": "https://docs.medusajs.com/resources/how-to-tutorials/tutorials/first-purchase-discounts",
                   "children": []
                 },
+                {
+                  "loaded": true,
+                  "isPathHref": true,
+                  "type": "ref",
+                  "title": "Implement Pre-Orders",
+                  "path": "https://docs.medusajs.com/resources/how-to-tutorials/tutorials/preorder",
+                  "children": []
+                },
                 {
                   "loaded": true,
                   "isPathHref": true,