{
  "fixture": "synthetic; no AI generation",
  "audio": {
    "ok": true,
    "kind": "audio",
    "duration_seconds": 1.0,
    "bytes": 32044
  },
  "sha256": {
    "sample.epub": "ca4b05baf6724ead39962490003234dff484825b29426cca66879315ec4ca820",
    "tone.wav": "6584051260619346b6cc1fbb108aaf7fa6b86cc35f64ecd2032f7d43f34f93cc"
  }
}