List customers

curl --request GET \
  --url https://api.kapso.ai/platform/v1/customers \
  --header 'X-API-Key: <api-key>'

{
  "data": [
    {
      "id": "550e8400-e29b-41d4-a716-446655440000",
      "name": "Acme Corp",
      "external_customer_id": "cus_abc123",
      "created_at": "2025-01-15T10:00:00Z",
      "updated_at": "2025-01-15T10:00:00Z"
    },
    {
      "id": "7c9e6679-7425-40de-944b-e07fc1f90ae7",
      "name": "TechStart Inc",
      "external_customer_id": "cus_xyz789",
      "created_at": "2025-01-14T15:30:00Z",
      "updated_at": "2025-01-14T15:30:00Z"
    }
  ],
  "meta": {
    "page": 1,
    "per_page": 20,
    "total_pages": 1,
    "total_count": 2
  }
}