Stellar signing

{
  "network": "Stellar",
  "kind": "Transaction",
  "transaction": "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"
}

import { Asset, BASE_FEE, Horizon, Networks, Operation, TransactionBuilder } from '@stellar/stellar-sdk'

const walletId = 'wa-6lbfv-9esgj-xxxxxxxxxxxxxxxx'
const wallet = await dfnsClient.wallets.getWallet({ walletId })

const provider = new Horizon.Server(process.env.HORIZON_API_URL!)

const account = await provider.loadAccount(senderWallet.address)
const transaction = new TransactionBuilder(account, {
  fee: BASE_FEE,
  networkPassphrase: Networks.TESTNET,
})
  .addOperation(
    Operation.payment({
      destination: 'GAZWLHTNAOJWW52GZCUJAS5MSXK7LAWCUC5TFOFFVDQ7CDTNFODJ37GB',
      asset: Asset.native(),
      amount: '1',
    })
  )
  .setTimeout(180)
  .build()

const res = await dfnsClient.wallets.generateSignature({
  walletId,
  body: {
    kind: 'Transaction',
    transaction: `0x${transaction.toEnvelope().toXDR('hex')}`,
  },
})