Zitadel first boot completed on 2026-10-26, so set FirstInstance.Skip: true and
initJob.enabled: false. Without Skip, every sync re-runs machinekeyWriter and
silently rotates the iam-admin key that terraform/zitadel authenticates with.
Also wire wireguard_allowed_cidr into the WireGuard security-group rule; the
variable was declared but the rule still used relay_admin_cidr, which blocks
the homelab peer unless its egress address happens to match the operator CIDR.