Feat: Centralized Access Control on Self Hosted Frappe Server

We should be able to utilize centralized Access Control features on self-hosted frappe builders, restriction will lead to people not using it much, as big projects require various permissions per person and ssh access.

Start by reviewing how access control currently works for self-hosted Frappe builders and how permissions are assigned per person. Clarify the centralized-control requirements and the role of SSH access; done should mean that large projects can manage varied user permissions without relying on direct server access.

Written by the indexing model from the issue text.