Improve message filtering

[yosbelms]

To filter logs currently it is necessary to parse the messages that it passed to ROARR.write in JSON format, resulting in a potentially CPU-intensive filtering logic.

My proposal is to pass unserialized message as second parameter to ROARR.write to avoid JSON parsing for each log message.

Context: gajus/slonik#277

[gajus]

This needs to be opt-in, because the serializer that Roarr uses is part of the magic that makes Roarr so fast.