docs: integrate shipstation guide (#10623)

* first draft

* finalized first draft + added link to sidebar

* fix lint errors

* type changes

* updates to createFulfillment

* updates

* more updates

* add package weight

* added note about package

* fix up order items fulfillment

* add meta image

* address comment

www/apps/resources/sidebar.mjs

@@ -575,6 +575,11 @@ export const sidebar = sidebarAttachHrefCommonOptions([
                 path: "/references/fulfillment/provider",
                 title: "Create Fulfillment Provider Module",
               },
+              {
+                type: "link",
+                path: "/integrations/guides/shipstation",
+                title: "Integrate ShipStation",
+              },
             ],
           },
           {
@@ -1794,6 +1799,17 @@ export const sidebar = sidebarAttachHrefCommonOptions([
           },
         ],
       },
+      {
+        type: "category",
+        title: "Fulfillment",
+        children: [
+          {
+            type: "link",
+            path: "/integrations/guides/shipstation",
+            title: "ShipStation",
+          },
+        ],
+      },
       {
         type: "category",
         title: "Notification",