curl --request GET \
  --url https://api.mixpeek.com/v1/analytics/indexes/usage \
  --header 'Authorization: <authorization>' \
  --header 'X-Namespace: <x-namespace>'

{
  "namespace_id": "<string>",
  "period": "<string>",
  "fields": [
    {
      "field_name": "<string>",
      "query_count": 123,
      "unique_queries": 123,
      "is_indexed": true,
      "is_protected": true,
      "avg_latency_ms": 123,
      "p95_latency_ms": 123,
      "first_seen": "2023-11-07T05:31:56Z",
      "last_seen": "2023-11-07T05:31:56Z"
    }
  ],
  "total_fields": 123,
  "indexed_fields": 123,
  "unindexed_fields": 123
}