docs: general fixes and overall changes (#7258)

* editing halfway

* edited second half

* adjust starter steps

* fix build

* typo fix

www/apps/book/app/basics/commerce-modules/page.mdx

@@ -45,4 +45,8 @@ export const GET = async (
 
 When you resolve the `ModuleRegistrationName.PRODUCT` (or `productModuleService`) registration name, you're actually resolving the main service of the Product Module.
 
+<Note title="Tip">
+
 To resolve the main service of any commerce module, use the `ModuleRegistrationName` enum imported from `@medusajs/modules-sdk` to refer to its registration name in the Medusa container.
+
+</Note>