Add a New Profileevent Merge That Counts the Number of Launched Background Merges

Why it matters

This feature provides visibility into the internal background merges by counting how many merge operations have been started, helping users monitor and analyze merge activities which impact performance and resource usage.

How to use it

Users can enable this feature by monitoring the Merge event in profile event counters. It is automatically integrated into the existing profiling metrics, and can be accessed via system tables or performance profiling tools.