[
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    "journey_step": "onboarding_start",
    "sent_at": "2026-09-06T10:12",
    "opened": true,
    "landing_surface": "앱 화면",
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  },
  {
    "send_id": "S-88205",
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    "journey_step": "sensor_attach_d0",
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    "landing_surface": "앱 화면",
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  },
  {
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    "landing_surface": null,
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  },
  {
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    "landing_surface": "웹 화면",
    "device_os": "iOS"
  },
  {
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    "journey_step": "glucose_spike_alert",
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  },
  {
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    "landing_surface": null,
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  },
  {
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    "landing_surface": "앱 화면",
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  },
  {
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    "landing_surface": "앱 화면",
    "device_os": "Android"
  },
  {
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    "landing_surface": null,
    "device_os": "Android"
  },
  {
    "send_id": "S-88330",
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    "journey_step": "meal_log_nudge",
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    "opened": true,
    "landing_surface": "앱 화면",
    "device_os": "Android"
  },
  {
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    "landing_surface": null,
    "device_os": "Android"
  },
  {
    "send_id": "S-88349",
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    "journey_step": "meal_log_nudge",
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    "landing_surface": null,
    "device_os": "Android"
  },
  {
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    "user_id": "U-2277",
    "journey_step": "meal_log_nudge",
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    "landing_surface": null,
    "device_os": "Android"
  },
  {
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    "journey_step": "onboarding_start",
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    "opened": true,
    "landing_surface": "앱 화면",
    "device_os": "iOS"
  },
  {
    "send_id": "S-88281",
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    "journey_step": "sensor_attach_d0",
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    "landing_surface": "앱 화면",
    "device_os": "iOS"
  },
  {
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    "landing_surface": "앱 화면",
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  },
  {
    "send_id": "S-88370",
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    "journey_step": "glucose_spike_alert",
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    "landing_surface": null,
    "device_os": "iOS"
  },
  {
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    "landing_surface": "앱 화면",
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  },
  {
    "send_id": "S-88295",
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    "journey_step": "sensor_attach_d0",
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    "opened": true,
    "landing_surface": "앱 화면",
    "device_os": "Android"
  },
  {
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    "journey_step": "sensor_attach_d3",
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    "opened": true,
    "landing_surface": "앱 화면",
    "device_os": "Android"
  },
  {
    "send_id": "S-88325",
    "user_id": "U-4408",
    "journey_step": "first_report",
    "sent_at": "2026-09-08T09:55",
    "opened": true,
    "landing_surface": "웹 화면",
    "device_os": "Android"
  },
  {
    "send_id": "S-88374",
    "user_id": "U-4408",
    "journey_step": "meal_log_nudge",
    "sent_at": "2026-09-09T12:40",
    "opened": true,
    "landing_surface": "앱 화면",
    "device_os": "Android"
  },
  {
    "send_id": "S-88380",
    "user_id": "U-4408",
    "journey_step": "sleep_tip",
    "sent_at": "2026-09-09T21:00",
    "opened": true,
    "landing_surface": "앱 화면",
    "device_os": "Android"
  },
  {
    "send_id": "S-88390",
    "user_id": "U-4408",
    "journey_step": "kit_reorder",
    "sent_at": "2026-09-09T09:10",
    "opened": false,
    "landing_surface": null,
    "device_os": "Android"
  },
  {
    "send_id": "S-88395",
    "user_id": "U-5510",
    "journey_step": "onboarding_start",
    "sent_at": "2026-09-09T09:00",
    "opened": true,
    "landing_surface": "앱 화면",
    "device_os": "iOS"
  },
  {
    "send_id": "S-88402",
    "user_id": "U-5510",
    "journey_step": "waist_measure",
    "sent_at": "2026-09-09T16:20",
    "opened": false,
    "landing_surface": null,
    "device_os": "iOS"
  }
]