docs: Add CATEGORIES support to App Extensions documentation

docs/integrations/apps/app-extensions/glossary.mdx

@@ -13,14 +13,15 @@ An App Extension's **context** describes the control panel location where the Ex
 
 ## Model
 
-An App Extension's **model** describes the control panel view it extends. Currently, App Extensions apply to the **View All** page of an API entity. There are currently three possible models:
+An App Extension's **model** describes the control panel view it extends. Currently, App Extensions apply to the **View All** page of an API entity. There are currently multiple possible models:
 
 | Enum | Description |
 |:-----|:------------|
 | `PRODUCTS` | App Extension menu items render in the **Action** menu for each product on the **[View Products](https://login.bigcommerce.com/deep-links/manage/products)** page. |
 | `PRODUCT_DESCRIPTION` | App Extension menu items render in the **Action** menu within Description section on the **[Edit a Product](https://login.bigcommerce.com/deep-links/manage/products/edit)** page. |
 | `ORDERS` | App Extension menu items render in the **Action** menu for each order on the **[View Orders](https://login.bigcommerce.com/deep-links/manage/orders)** page. |
 | `CUSTOMERS` | App Extension menu items render in the **Action** menu for each customer on the **[View Customers](https://login.bigcommerce.com/deep-links/manage/customers)** page. |
+| `CATEGORIES` | App Extension menu items render in the **Action** menu for each category on the **[View Categories](https://login.bigcommerce.com/deep-links/manage/products/categories)** page and on the Edit Category page. |
 
 ## Label
 

docs/integrations/apps/app-extensions/guide.mdx

@@ -315,6 +315,13 @@ The [Store appExtensions](/graphql-admin/reference#query-store) query returns a
                   "url": "/customers/${id}/interactions",
                   "model": "CUSTOMERS"
                 }
+              },
+              {
+                "node": {
+                  "id": "bc/store/appExtension/4",
+                  "url": "/categories/${id}",
+                  "model": "CATEGORIES"
+                }
               }
             ]
           }

docs/integrations/apps/app-extensions/index.mdx

@@ -216,7 +216,7 @@ Each App Extension is associated with one control panel page, which you define u
 For supported models, see the [App Extensions Glossary](/docs/integrations/apps/app-extensions/glossary) and the [GraphQL Admin API Reference](/graphql-admin/reference).
 
 <Callout type="info">
- There is a **limit** of two App Extensions per app, per [model](/docs/integrations/apps/app-extensions/glossary#model). Your app can register up to two App Extensions for the orders model, two for the products model, and two for customers. If these limits are detrimental to your use case or user experience, please reach out through our [Developer Community](/community).
+ There is a **limit** of two App Extensions per app, per [model](/docs/integrations/apps/app-extensions/glossary#model). Your app can register up to two App Extensions for the orders model, two for the products model, two for customers, and two for categories. If these limits are detrimental to your use case or user experience, please reach out through our [Developer Community](/community).
 </Callout>
 
 
@@ -253,6 +253,15 @@ The App Extensions feature unlocks new use cases. The following sections organiz
 * Expose the whole product object, including metafields, for control panel users to view and edit.
 * Expose a third-party product configurator that uses an ERP or PIM system as the source of truth, then use the Catalog API to sync with BigCommerce and resolve any errors.
 
+### View Categories and Edit Category
+
+* Manage category hierarchy and relationships in a custom interface.
+* Expose the whole category object, including metafields, for control panel users to view and edit.
+* Sync category data with a third-party PIM or CMS system, then use the Catalog API to sync with BigCommerce and resolve any errors.
+* Provide category-specific analytics or insights from external systems.
+* Add bulk operations to category rows on the list page.
+* Extend category editing workflows with custom tools on the edit page.
+
 ## Using App Extensions in public apps
 
 Public apps that use App Extensions have the following additional requirements for approval: