Make OpFromGraph available at root scope

[ricardoV94]

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📚 Documentation preview 📚: https://pytensor--1113.org.readthedocs.build/en/1113/

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.10%. Comparing base (9858b33) to head (53dcf70).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1113   +/-   ##
=======================================
  Coverage   82.10%   82.10%           
=======================================
  Files         185      185           
  Lines       48130    48130           
  Branches     8669     8669           
=======================================
  Hits        39519    39519           
  Misses       6444     6444           
  Partials     2167     2167           

[jessegrabowski]

Huge change, I think we should get consensus from all core devs before merging