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{  "responses": [    {      "requestId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",      "briefId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",      "briefTitle": "How to choose running shoes",      "invitationId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",      "expertEmail": "jane.doe@acme.com",      "completedAt": "2026-05-25T10:30:00.000Z",      "questions": [        {          "questionId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",          "sectionTitle": "Finding your fit",          "question": "What factors matter most when choosing running shoes?",          "answer": "Gait and cushioning are the two biggest factors.",          "answeredAt": "2026-05-25T10:30:00.000Z"        }      ]    }  ]}