docs: general fixes and improvements (#7918)

* docs improvements and changes

* updated module definition

* modules + dml changes

* fix build

* fix vale error

* fix lint errors

* fixes to stripe docs

* fix condition

* fix condition

* fix module defintion

* fix checkout

* disable UI action

* change oas preview action

* flatten provider module options

* fix lint errors

* add module link docs

* pr comments fixes

* fix vale error

* change node engine version

* links -> linkable

* add note about database name

* small fixes

* link fixes

* fix response code in api reference

* added migrations step

www/apps/book/app/architectural-modules/page.mdx

@@ -0,0 +1,32 @@
+export const metadata = {
+  title: `${pageNumber} Architectural Modules`,
+}
+
+# {metadata.title}
+
+In this chapter, you’ll learn about architectural modules.
+
+## What is an Architectural Module?
+
+An architectural module implements features and mechanisms related to the Medusa application’s architecture and infrastructure.
+
+Since modules are interchangeable, you have more control over Medusa’s architecture. For example, you can choose to use Memcached for event handling instead of Redis.
+
+---
+
+### Architectural Module Type
+
+There are different architectural module types including:
+
+![Diagram illustrating how the modules connect to third-party services](https://res.cloudinary.com/dza7lstvk/image/upload/v1716197340/Medusa%20Book/architectural-modules_bj9bb9.jpg)
+
+- Cache Module: Defines the caching mechanism or logic to cache computational results.
+- Event Module: Integrates a pub/sub service to handle subscribing to and emitting events.
+- File Module: Integrates a storage service to handle uploading and managing files.
+- Notification Module: Integrates a third-party service or defines custom logic to send notifications to users and customers.
+
+---
+
+## Architectural Modules List
+
+Refer to the [Architectural Modules reference](!resources!/architectural-modules) for a list of Medusa’s architectural modules, available modules to install, and how to create an architectural module.