Issue in /src/pages/guides/getting-started/permissions.md

Clarify permissions necessary for content copy (i.e. operations related to content flow and content set). According to https://experienceleague.adobe.com/docs/experience-manager-cloud-manager/content/using/content-copy.html?lang=en#permissions this seems to require the "Deployment Manager" role.

Open src/pages/guides/getting-started/permissions.md and compare its content-copy permissions guidance with the linked Adobe Experience Manager documentation. Update the guidance to clarify whether the Deployment Manager role is required for content flow and content set operations; the permission requirement should be explicit when done.

索引モデルが issue の本文から書いたものです。