Silo the first field of public logs

[nventuro]

#10210 introduced siloing of the first field of private logs by having the private kernel hash it with the contract address. This is a very powerful primitive, as it cheaply lets contracts verify that a given log was indeed emitted by a certain contract, and so we can safely process them in order to do note discovery, message processing, etc.

However, this does not currently happen for logs emitted in public. encrypted_logs/payload.nr was modified to make partial note logs computed in private (which are only emitted in public) manually perform said siloing in the app, behaving as if the AVM was doing it. Even though we don't really need for public logs to have said siloing since they're public already and can be verified via alternative means, it'd be better if all logs looked the same, particularly when it comes to message delivery via tags (#9373) as not having this would mean we'd need to deal with multiple tagging schemes.