feat(carddav): fix issue where only personal contacts can be synced on macOS (#1981). When , append the addressbook name as a username suffix to force macOS to treat each book as a distinct account. Usernames must not contain . Install via the provisioning profile. Closes #6033.

SoObjects/SOGo/SOGoSystemDefaults.m

@@ -588,6 +588,11 @@ _injectConfigurationFromFile (NSMutableDictionary *defaultsDict,
   return [self boolForKey: @"SOGoAddressBookDAVAccessEnabled"];
 }
 
+- (BOOL) carddavSingleAddressBookProfile
+{
+  return [self boolForKey: @"SOGoCarddavSingleAddressBookProfile"];
+}
+
 - (BOOL) enableEMailAlarms
 {
   return [self boolForKey: @"SOGoEnableEMailAlarms"];