[logback-user] separate task log files (slf4j + logback)

The MDC does not help when I have several different long-running tasks in one thread and I just want to immediately separate their logs. It seems that this is not such a fantastic wish. It is much easier to separate logical logging flows at once, than to filter them later in databases. The amount of data is large, logs per day can accumulate several hundred megabytes. It turns out that we will have to write our own implementation of such a log.