curl -X GET '/unified-transactions/list?page=1&limit=20' \
  -H 'Authorization: Bearer YOUR_ACCESS_TOKEN'

{
  "success": true,
  "data": {
    "transactions": [
      {
        "transaction_id": "utx_01abc123",
        "type": "deposit",
        "status": "completed",
        "amount": "500.00",
        "asset": "USDC",
        "chain": "solana",
        "from_address": "7xKXtg2CW87d...",
        "to_address": "GY1EZGdpiJNyx...",
        "tx_hash": "5xYz...",
        "fee_amount": "0.00",
        "created_at": "2026-03-26T10:00:00Z"
      },
      {
        "transaction_id": "utx_02def456",
        "type": "card_transaction",
        "status": "completed",
        "amount": "25.99",
        "asset": "EUR",
        "service_data": {
          "merchant_name": "Amazon",
          "card_last_four": "4242"
        },
        "created_at": "2026-03-26T11:00:00Z"
      }
    ],
    "pagination": {
      "page": 1,
      "limit": 20,
      "total": 150
    }
  }
}