add ability to set uo log output

**Is your feature request related to a problem? Please describe.**
Add ability to set up logging output. We run project on google cloud and we use google log explorer for logging collection. When log appear in stderr it marks like severity:ERROR

**Describe the solution you'd like**
By default golang log write to stderr. To change output we can use log.SetOutput

**Describe alternatives you've considered**
I'm open for any other solutions, thanks


Start by locating where the Go project configures or emits logs, then review how the standard log package and log.SetOutput could fit that setup. Confirm the expected configuration surface and logging behavior before changing anything; done means callers can select an output other than stderr without breaking existing logging.

Written by the indexing model from the issue text.