Downlink acknowledged

When receiving this message we known the network server has successfully sent the downlink to the gateway.

{
  "timestamp": 1680203083384,
  "type": "downlink_acknowledged",
  "meta": {
    "application": "61cc747fdbb07352dbd89e74",
    "gateway": "fedcba9876543210",
    "device": "0123456789abcdef",
    "packet_id": "2551457619",
    "application_name": "FH",
    "organization_name": "Volvo",
    "device_name": "Demo device",
    "device_tags": ["tag-abc", "tag-xyz"],
    "gateway_tags": ["tag-abc", "tag-xyz"],
    "time": 1680203083.384
  },
  "params": {
    "port": 100,
    "payload": "aabb",
    "counter_down": 1,
    "radio": {
      "freq": 924.5,
      "modulation": {
        "bandwidth": 500,
        "spreading": 7,
        "coderate": "CR_4_5",
        "inverted": true
      }
    }
  }
}