I'm trying to understand the implementation of Steller in TrustWallet core. There are a number of fields added to a signed message in this changeset. Where is the documentation that describes the format of this data?
What is encoded in the change set is the XDR of assets and operations, you can find the details here: https://github.com/stellar/js-stellar-base/blob/master/xdr/curr/Stellar-transaction.x https://github.com/stellar/js-stellar-base/blob/master/xdr/curr/Stellar-ledger-entries.x
For a higher level, you can find the operation list here: https://developers.stellar.org/docs/start/list-of-operations