docs: Add changelog for SEP stable release

[MuyangAmigo]

No description provided.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.61%. Comparing base (56107d2) to head (873f1cb).
Report is 2 commits behind head on release/5.10.0.

Additional details and impacted files

@@               Coverage Diff               @@
##           release/5.10.0   #12383   +/-   ##
===============================================
  Coverage           94.61%   94.61%           
===============================================
  Files                 582      582           
  Lines               34494    34494           
  Branches             6788     6793    +5     
===============================================
  Hits                32638    32638           
  Misses               1582     1582           
  Partials              274      274           

[sffamily]

But shall we hold on this given the all the Copilot names changed to Agent? so we just did one shot to avoid another major change after this?