docs: fix information related to link directions (#8236)

* docs: fix keys passed to remoteLink.create and remoteLink.dismiss

* updated hello module name + clarified note

* added details about module link directions

* fix lint errors

www/apps/book/app/advanced-development/modules/module-link-directions/page.mdx

@@ -0,0 +1,61 @@
+export const metadata = {
+  title: `${pageNumber} Module Link Direction`,
+}
+
+# {metadata.title}
+
+In this chapter, you'll learn about difference in module link directions, and which to use based on your use case.
+
+## Link Direction
+
+The module link's direction depends on the order you pass the data model configuration parameters to `defineLink`.
+
+For example, the following defines a link from the `helloModuleService`'s `myCustom` data model to the Product Module's `product` data model:
+
+```ts
+export default defineLink(
+  HelloModule.linkable.myCustom,
+  ProductModule.linkable.product
+)
+```
+
+Whereas the following defines a link from the Product Module's `product` data model to the `helloModuleService`'s `myCustom` data model:
+
+```ts
+export default defineLink(
+  ProductModule.linkable.product,
+  HelloModule.linkable.myCustom
+)
+```
+
+The above links are two different links that serve different purposes.
+
+---
+
+## Which Link Direction to Use?
+
+### Extend Data Models
+
+If you're adding a link to a data model to extend it and add new fields, define the link from the main data model to the custom data model.
+
+For example, if the `myCustom` data model adds new fields to the `product` data model, define the link from `product` to `myCustom`:
+
+```ts
+export default defineLink(
+  ProductModule.linkable.product,
+  HelloModule.linkable.myCustom
+)
+```
+
+### Associate Data Models
+
+If you're linking data models to indicate an association between them, define the link from the custom data model to the main data model.
+
+For example, if the `myCustom` data model is associated to the `product` data model, define the link from `myCustom` to `product`:
+
+```ts
+export default defineLink(
+  HelloModule.linkable.myCustom,
+  ProductModule.linkable.product
+)
+```

www/apps/book/app/advanced-development/modules/module-links/page.mdx

@@ -51,8 +51,8 @@ import ProductModule from "@medusajs/product"
 import { defineLink } from "@medusajs/utils"
 
 export default defineLink(
-  HelloModule.linkable.myCustom,
-  ProductModule.linkable.product
+  ProductModule.linkable.product,
+  HelloModule.linkable.myCustom
 )
 ```
 
@@ -86,11 +86,11 @@ import ProductModule from "@medusajs/product"
 import { defineLink } from "@medusajs/utils"
 
 export default defineLink(
+  ProductModule.linkable.product,
   {
     linkable: HelloModule.linkable.myCustom,
     isList: true,
-  },
-  ProductModule.linkable.product
+  }
 )
 ```
 
@@ -132,11 +132,11 @@ import ProductModule from "@medusajs/product"
 import { defineLink } from "@medusajs/utils"
 
 export default defineLink(
+  ProductModule.linkable.product,
   {
     linkable: HelloModule.linkable.myCustom,
     deleteCascades: true,
-  },
-  ProductModule.linkable.product
+  }
 )
 ```
 

www/apps/book/app/advanced-development/modules/remote-link/page.mdx

@@ -61,7 +61,7 @@ await remoteLink.create({
   [Modules.PRODUCT]: {
     product_id: "prod_123",
   },
-  "hello": {
+  "helloModuleService": {
     my_custom_id: "mc_123",
   },
 })
@@ -69,6 +69,12 @@ await remoteLink.create({
 
 The `create` method accepts as a parameter an object. The object’s keys are the names of the linked modules.
 
+<Note title="Important">
+
+The keys (names of linked modules) must be in the same direction of the link definition.
+
+</Note>
+
 The value of each module’s property is an object, whose keys are of the format `{data_model_snake_name}_id`, and values are the IDs of the linked record.
 
 So, in the example above, you link a record of the `MyCustom` data model in a `hello` module to a `Product` record in the Product Module.
@@ -90,7 +96,7 @@ await remoteLink.dismiss({
   [Modules.PRODUCT]: {
     product_id: "prod_123",
   },
-  "hello": {
+  "helloModuleService": {
     my_custom_id: "mc_123",
   },
 })
@@ -98,6 +104,12 @@ await remoteLink.dismiss({
 
 The `dismiss` method accepts the same parameter type as the [create method](#create-link).
 
+<Note title="Important">
+
+The keys (names of linked modules) must be in the same direction of the link definition.
+
+</Note>
+
 ---
 
 ## Cascade Delete Linked Records

www/apps/book/sidebar.mjs

@@ -114,6 +114,10 @@ export const sidebar = sidebarAttachHrefCommonOptions(
               path: "/advanced-development/modules/module-links",
               title: "Module Links",
             },
+            {
+              path: "/advanced-development/modules/module-link-directions",
+              title: "Module Link Direction",
+            },
             {
               path: "/advanced-development/modules/remote-link",
               title: "Remote Link",