Add "User Only" Permission for Editing Names on Person Sidebar

We’re introducing a "User Only" permission setting that restricts who can edit names in the Person Sidebar.

With this update:

• Only the user themselves (not other team members) will be able to change their display name

• Helps maintain consistency in user identity across workspaces

• Prevents accidental or unauthorized edits by others

This is especially useful for large teams, clients, or orgs that require clear ownership and identity control in collaborative workspaces.