With the old schema, it is impossible to tell which operations emitted which events. This is not an issue now, as there is only one operation in soroban txns, but if we support multiple in future, it would be an issue. To prevent that we can change the events field to be a list of lists (one list per operation).

Two questions:

• Anywhere else we need to update this? (aside from propagating it through core/soroban-cli/go/js/etc...)
• Do we need the OperationEvents struct? Is there a simpler way to do an inline nested list?