ep: Change kept_rate definition to a more intuitive one (#54306)

This change contains a number of fixes to make kept_rate more intuitive.
It also adds a CLI utility to print debug info on how the metric is
computed.

Release Notes:

- N/A
72b41263f3Oleksiy Syvokon committed on 4/20/2026, 11:03:26 AM· committed by GitHubparentf92178e
8 files changedLine totals unavailable