Consistency issues in Settlement Response spec

[kladkogex]

The Settlement Response specification has a few minor inconsistencies that could be improved:

Field Name	Type	Required	Description
success	boolean	Required	Indicates whether the payment settlement was successful
errorReason	string	Optional	Error reason if settlement failed (omitted if successful)
transaction	string	Required	Blockchain transaction hash (empty string if settlement failed)
network	string	Required	Blockchain network identifier
payer	string	Required	Address of the payer's wallet

1. Since errorReason is optional, the transaction field should also be optional rather than set to an empty string.

2. The payer field should also be optional in case of an error. This is because a malformed or missing payer value in the payload might prevent the server from returning a valid address.