Depending on the type of the transaction: "transactionTypeId", a different object will be given in the transaction.
If it's a lightning invoice, the "invoice" object will be in the response.
If it's a lightning payment, the "payment" object will be in the response.
If it's an OnChain transaction (receive or send), the "onChainTransaction" object will be in the response.
See the Transaction Types Table.
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