docs: Update domain Public API documentation

lib/accounts/accounts.ex

@@ -1,6 +1,15 @@
 defmodule Mv.Accounts do
   @moduledoc """
   AshAuthentication specific domain to handle Authentication for users.
+
+  ## Resources
+  - `User` - User accounts with authentication methods (password, OIDC)
+  - `Token` - Session tokens for authentication
+
+  ## Public API
+  The domain exposes these main actions:
+  - User CRUD: `create_user/1`, `list_users/0`, `update_user/2`, `destroy_user/1`
+  - Authentication: `create_register_with_rauthy/1`, `read_sign_in_with_rauthy/1`
   """
   use Ash.Domain,
     extensions: [AshAdmin.Domain, AshPhoenix]