Get campaign products

curl https://api.interchange.io/api/v2/buyer/campaigns/cmp_987654321/products \
  -H "Authorization: Bearer $SCOPE3_API_KEY"

{
  "campaignId": "cmp_987654321",
  "discoveryId": "disc_abc123",
  "products": [
    {
      "productId": "prod_xyz789",
      "productName": "Example Media - CTV Premium",
      "salesAgentId": "agent_example",
      "selectedAt": "2026-05-01T10:00:00Z",
      "mediaBuys": [
        {
          "mediaBuyId": "mb_abc123",
          "name": "Example Media buy",
          "status": "ACTIVE",
          "packageIds": ["pkg_video_15s", "pkg_video_30s"]
        }
      ]
    }
  ],
  "searchContexts": [
    {
      "id": "ctx_abc",
      "brief": "Premium video for tech-savvy professionals",
      "channels": ["ctv"],
      "countries": ["US"],
      "createdAt": "2026-05-01T09:30:00Z",
      "productCount": 1
    }
  ],
  "summary": {
    "totalProducts": 1,
    "productsOnMediaBuys": 0,
    "productsPending": 1
  }
}