{
  "external_inventory_id": "DEMO-STOCK-001",
  "observed_at": "2030-01-01T10:00:00Z",
  "reported_available_quantity": 25,
  "source_event_id": "demo-stock-event-000001",
  "source_sequence": 1,
  "source_system": "partner_demo",
  "valid_until": "2030-01-01T11:00:00Z"
}