Metrics for casts

curl --request GET \
  --url https://api.neynar.com/v2/farcaster/cast/metrics \
  --header 'x-api-key: <api-key>'

{
  "metrics": [
    {
      "start": "2023-11-07T05:31:56Z",
      "resolution_in_seconds": 123,
      "cast_count": 123
    }
  ]
}