Api Points Transactions Summary Retrieve

GET /api/points-transactions/summary/ Get the caller's own organization's Respan Points balance + USD book value (mirrors ``/api/credit-transactions/summary/``). Own-org only — including superadmins. There is NO ``?org=`` cross-org override (dropped to eliminate the cross-tenant leak / unknown-org bug class). The org is resolved via ``ProjectScopedQuerysetMixin``'s ``get_request_project_id()``; an unresolvable own org FAILS CLOSED to a zero-balance 200 (consistent with the list endpoint's empty result), NOT a 404. Response: { "unique_organization_id": "...", "points_balance": 1200.0, "usd_book_value": 12.0, "last_points_event_at": "..." # null when the org has no points }