chore: reorganize docs apps (#7228)

* reorganize docs apps

* add README

* fix directory

* add condition for old docs

www/apps/user-guide/app/customers/groups/page.mdx

@@ -0,0 +1,88 @@
+---
+sidebar_position: 2
+---
+
+import { EllipsisHorizontal } from "@medusajs/icons"
+
+export const metadata = {
+  title: `Manage Customer Groups`,
+}
+
+# {metadata.title}
+
+In this document, you’ll learn how to manage customer groups, including customers in these groups.
+
+## Create a Customer Group
+
+To create a customer group:
+
+1. Go to the Customers → Customer Groups page.
+2. Click the Create button.
+3. In the form that opens, enter the customer group's name.
+4. Click the Create button.
+
+---
+
+## View Customer Group Details
+
+To view the details of a customer group:
+
+1. Go to the Customers → Customer Groups page.
+2. Click on the group you want to view.
+
+---
+
+## Edit a Customer Group
+
+To edit a customer group:
+
+1. Go to the customer group’s details page.
+2. Click on the <InlineIcon Icon={EllipsisHorizontal} alt="three-dots" /> icon at the top right of the first section.
+3. Click on Edit in the dropdown.
+4. In the drawer that opens, edit the group's name.
+5. Once you’re done, click on the Edit Group button.
+
+---
+
+## Manage Customers in a Group
+
+### View List of Customers in a Group
+
+To view the list of customers in a customer group:
+
+1. Go to the customer group’s details page.
+2. Under the Customers section, you’ll find all customers that belong to this customer group.
+
+### Add Customers to a Group
+
+To add customers to a customer group:
+
+1. Go to the customer group’s details page.
+2. Under the Customers section, click the Add button at the top right.
+3. Check the box next to every customer you want to add to the group.
+4. Once you're done, click on the Add button.
+
+### Remove a Customer from a Group
+
+To remove customers from a customer group:
+
+1. Go to the customer group’s details page.
+2. Under the Customer section, click the <InlineIcon Icon={EllipsisHorizontal} alt="three-dots" /> icon next to the customer you want to remove from the group.
+3. Choose Remove from the dropdown.
+4. Confirm removing the customer by clicking the Continue button in the pop-up.
+
+---
+
+## Delete Customer Group
+
+<Note type="warning">
+
+Deleting a customer group is irreversible.
+
+</Note>
+
+To delete a customer group:
+
+1. Go to the customer group’s details page.
+2. Click the <InlineIcon Icon={EllipsisHorizontal} alt="three-dots" /> icon at the top right of the first section.
+3. Choose Delete from the dropdown.