curl --request GET \
  --url http://localhost:8000/api/sessions/{session_id}/cost-breakdown

{
  "session_id": "<string>",
  "total_cost": "<string>",
  "events": [
    {
      "id": "<string>",
      "session_id": "<string>",
      "user_id": "<string>",
      "provider": "<string>",
      "event_type": "stt_minutes",
      "quantity": "<string>",
      "unit_cost": "<string>",
      "total_cost": "<string>",
      "created_at": "2023-11-07T05:31:56Z",
      "agent_id": "<string>"
    }
  ],
  "cost_by_type": {}
}