docs: add section on how to retrieve user list (#17798)

previews
- [admin/users](https://coder.com/docs/@export-coder-users/admin/users)
-
[reference/cli/users](https://coder.com/docs/@export-coder-users/reference/cli/users)

followup to slack thread:

> Tim
> what's the best way for customers to export a list of Coder users?
>
> @ericpaulsen
> the `/api/v2/users` API route returns all users in the deployment
(along with other information - email, status, username, etc.). from
<https://coder.com/docs/reference/api/users#get-users>


- adds an easy-to-find section to the admin/users doc
- updates the cli commands with short descriptions

---------

Co-authored-by: EdwardAngert <17991901+EdwardAngert@users.noreply.github.com>
Co-authored-by: M Atif Ali <atif@coder.com>

docs/reference/cli/users.md

@@ -17,8 +17,8 @@ coder users [subcommand]
 
 | Name                                             | Purpose                                                                               |
 |--------------------------------------------------|---------------------------------------------------------------------------------------|
-| [<code>create</code>](./users_create.md)         |                                                                                       |
-| [<code>list</code>](./users_list.md)             |                                                                                       |
+| [<code>create</code>](./users_create.md)         | Create a new user.                                                                    |
+| [<code>list</code>](./users_list.md)             | Prints the list of users.                                                             |
 | [<code>show</code>](./users_show.md)             | Show a single user. Use 'me' to indicate the currently authenticated user.            |
 | [<code>delete</code>](./users_delete.md)         | Delete a user by username or user_id.                                                 |
 | [<code>edit-roles</code>](./users_edit-roles.md) | Edit a user's roles by username or id                                                 |

docs/reference/cli/users_create.md

@@ -1,6 +1,8 @@
 <!-- DO NOT EDIT | GENERATED CONTENT -->
 # users create
 
+Create a new user.
+
 ## Usage
 
 ```console

docs/reference/cli/users_list.md

@@ -1,6 +1,8 @@
 <!-- DO NOT EDIT | GENERATED CONTENT -->
 # users list
 
+Prints the list of users.
+
 Aliases:
 
 * ls