docs: added + updated build and deployment guides (#10019)

www/apps/resources/sidebar.mjs

@@ -2100,7 +2100,18 @@ export const sidebar = sidebarAttachHrefCommonOptions([
           {
             type: "category",
             title: "Medusa Application",
-            autogenerate_path: "/deployment/medusa-application",
+            children: [
+              {
+                type: "link",
+                path: "https://docs.medusajs.com/learn/deployment/general",
+                title: "General"
+              },
+              {
+                type: "link",
+                path: "/deployment/medusa-application/railway",
+                title: "Railway"
+              },
+            ],
           },
           {
             type: "category",