{
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  "producerId": "chovy-server",
  "manifestId": "chovy-signup-discount-v1",
  "manifestRevision": 1,
  "participantId": "participant-opaque-7d12",
  "at": "2026-09-15T12:00:00Z",
  "id": "event-assignment-42",
  "kind": "assignment",
  "payload": {
    "assignmentId": "assignment-42",
    "variantId": "signup-10",
    "cohortId": "eligible-referred-customers"
  }
}