docs: change navbar items + breadcrumb improvements (#9209)

- Add a new commerce module navbar item
- Rename Learning Resources to Development Resources (in navbar and across documentation content)
- Improve breadcrumbs to show categories / subcategories

Preview: https://resources-docs-git-docs-navbar-changes-medusajs.vercel.app/v2/resources

www/apps/book/app/debugging-and-testing/testing-tools/integration-tests/page.mdx

@@ -72,7 +72,7 @@ This runs your Medusa application and runs the tests available under the `src/in
 
 ## Other Options and Inputs
 
-Refer to [this reference in the Learning Resources documentation](!resources!/test-tools-reference/medusaIntegrationTestRunner) for other available parameter options and inputs of the `testSuite` function.
+Refer to [this reference in the Development Resources documentation](!resources!/test-tools-reference/medusaIntegrationTestRunner) for other available parameter options and inputs of the `testSuite` function.
 
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@@ -80,7 +80,7 @@ Refer to [this reference in the Learning Resources documentation](!resources!/te
 
 The `medusaIntegrationTestRunner` function creates a database with a random name before running the tests. Then, it drops that database after all the tests end.
 
-To manage that database, such as changing its name or perform operations on it in your tests, refer to the [references in the Learning Resources documentation](!resources!/test-tools-reference/medusaIntegrationTestRunner).
+To manage that database, such as changing its name or perform operations on it in your tests, refer to the [references in the Development Resources documentation](!resources!/test-tools-reference/medusaIntegrationTestRunner).
 
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