Users complain that `warn` level produces lot of unnecessary logs.
+ join behavior logging is demoted to `trace`;
+ xor logging is demoted to `trace`;
+ service error logging is demoted to `debug`.
chore(execution-engine): Some stream-related LambdaError are unjoinable b/c: canon stream replaces normal stream, when canon stream is used, it is materialized and its size is known
`StreamDontHaveSuchGeneration` is a catchable error that could be caught by a xor instruction and then handled by a user. But it makes no sense because this error could arise only iff smth went wrong during merging or when data is corrupted.
