v20260113-193414

Change compiler regression report to median (#7648)

This change the logic to find the baseline of the compiler regression.

before it find the max metric value from past 3-6 days as baseline
value, and compare it to the latest 3 days metric values.
however, this create some noisy alert. Change it to median value , to
avoid some scenarios such as shown below


<img width="393" height="201" alt="image"
src="https://github.com/user-attachments/assets/edeff7f8-09a8-494e-8127-b3b0984a297f"
/>