curl --request GET \
  --url http://localhost:3000/api/v1/indices/{identifier}/companies \
  --header 'Authorization: Bearer <token>'

{
  "companies": [
    {
      "id": "comp_apple123",
      "name": "Apple Inc.",
      "slug": "apple-inc",
      "ticker_symbol": "VOLV-B.ST",
      "exchange": {
        "id": "<string>",
        "name": "<string>",
        "mic_code": "<string>"
      }
    }
  ],
  "pagination": {
    "count": 123,
    "next_cursor": "<string>"
  }
}