Api Points Transactions Retrieve

GET /api/points-transactions/<id>/ Retrieve a single Respan Points transaction by ID, scoped to the caller's own organization. Own-org only — including superadmins (no ``get_superadmin_queryset`` override). A row belonging to another org is not visible (404), enforced by ``ProjectScopedQuerysetMixin``. NOTE: CLICKHOUSE-ONLY — reads ``ch_billing_event`` points-class rows.