Replace image/vfolder/user-group-keypair ORM relationship usages with explicit queries and remove them

Replace remaining usages of ImageRow.aliases/registry_row, ImageAliasRow.image, VFolderRow.user_row/group_row, VFolderInvitationRow.vfolder_row, UserRow.resource_policy_row/keypairs/main_keypair/domain, GroupRow.resource_policy_row/users/sgroup_for_groups_rows, KeyPairRow.resource_policy_row/user_row, ScalingGroupRow.agents, ScalingGroupFor\*Row.sgroup_row, NotificationRuleRow.channel, RoleRow.object_permission_rows, and remaining artifact/registry/network/service-catalog referenced relationships with explicit queries via the repository/ops layer, then remove the relationship() definitions and dependent loader options.

JIRA Issue: BA-7228

Start by inventorying the listed ORM relationship usages and their dependent loader options, then trace each usage to the repository/ops layer. Replace the relationships with explicit queries and verify that the relationship() definitions and all dependent loader options can be removed across the affected models.

Written by the indexing model from the issue text.