Better log messages during configuration reload

Why it matters

This enhancement provides clearer and more informative log messages when the ClickHouse server reloads its configuration. It helps users and administrators better understand the reload process, diagnose issues faster, and maintain smoother operation.

How to use it

The improved logging takes effect automatically when the configuration is reloaded. Users can trigger a configuration reload using existing commands (e.g., sending the SIGHUP signal to the ClickHouse server) and will then see enhanced logs without any additional configuration changes.