curl --request GET \
  --url http://localhost:8000/api/v1/google-ads/campaigns \
  --header 'Authorization: Bearer <token>'

{
  "campaigns": [
    {
      "id": 123,
      "name": "<string>",
      "status": "<string>",
      "channel_type": "<string>",
      "start_date": "<string>",
      "end_date": "<string>",
      "budget": 123,
      "metrics": {
        "impressions": 123,
        "clicks": 123,
        "ctr": 123,
        "average_cost_per_conv": 123,
        "cost": 123,
        "conversions": 123,
        "conversion_rate": 123,
        "cost_per_conversion": 123,
        "impression_share": 123,
        "abs_top_page_rate": 123
      }
    }
  ],
  "storage_result": "<string>"
}