curl --request POST \
  --url https://api.portalhq.io/api/v3/clients/me/chains/{chain}/wallet/build-authorization-transaction \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "signature": "<string>",
  "subsidize": true,
  "contractAddress": "<string>",
  "nonce": 123,
  "txNonce": 123,
  "to": "<string>",
  "value": "<string>",
  "data": "<string>",
  "gas": "<string>",
  "gasLimit": "<string>",
  "maxFeePerGas": "<string>",
  "maxPriorityFeePerGas": "<string>"
}
'

{
  "data": {
    "transaction": {
      "type": "<string>",
      "from": "<string>",
      "to": "<string>",
      "value": "<string>",
      "data": "<string>",
      "nonce": "<string>",
      "chainId": "<string>",
      "gas": "<string>",
      "gasLimit": "<string>",
      "maxFeePerGas": "<string>",
      "maxPriorityFeePerGas": "<string>",
      "authorizationList": [
        {}
      ]
    },
    "transactionHash": "<string>"
  },
  "metadata": {
    "authorization": {},
    "chainId": "<string>",
    "subsidized": true
  }
}