[WIP] Add generator checks and differentiability checks to assert_valid

[astralcai]

[sc-65197]

[github-actions]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.69%. Comparing base (cbc5a9d) to head (872ca86).
Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #6282   +/-   ##
=======================================
  Coverage   99.69%   99.69%           
=======================================
  Files         443      443           
  Lines       42022    42031    +9     
=======================================
+ Hits        41894    41903    +9     
  Misses        128      128           

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