[
  {
    "id": "fixture-conv-aa1",
    "title": "Fixture conversation",
    "mapping": {
      "m1": {
        "message": {
          "author": { "role": "user" },
          "content": { "parts": ["Fixture user line for import test."] },
          "create_time": 1700000000
        }
      },
      "m2": {
        "message": {
          "author": { "role": "assistant" },
          "content": { "parts": ["Fixture assistant reply for import test."] },
          "create_time": 1700000001
        }
      }
    }
  }
]