[v.2.8.0] Release Tracker

[chuanqi129]

We cut a release branch for the 2.8.0 release.

Our plan from this point from this point is roughly:

• Phase 1 (until 7/7/25): work on finalizing the release branch
• Phase 2 (after 7/7/25): perform extended integration/stability/performance testing based on Release Candidate builds.

This issue is for tracking cherry-picks to the release branch.

Refer pytorch/pytorch#156745