1. Sitecore XM Cloud Documentation, "Manage users in your organization". This document states, "To invite a user to your organization, you must be an Organization Owner or an Organization Admin." It details the process of assigning roles, which happens in the Sitecore Cloud Portal.
2. Sitecore XM Cloud Documentation, "The roles in the Sitecore Cloud Portal". This page outlines the permissions for each role. It confirms that 'Organization Owner' and 'Organization Admin' can "Manage users, teams, and roles," which is the action required to grant a developer access to the Deploy App.
3. Sitecore XM Cloud Documentation, "Walkthrough: Inviting a new user to an organization". This guide illustrates the entire process, showing that user invitation and role assignment are performed by an Admin or Owner within the Sitecore Cloud Portal interface (specifically under Admin > User Management).