feat: refactor javascript generator

[akashrpo]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (961b872) 88.82% compared to head (3ca8c08) 88.82%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master      #13   +/-   ##
=======================================
  Coverage   88.82%   88.82%           
=======================================
  Files           3        3           
  Lines         170      170           
  Branches       58       58           
=======================================
  Hits          151      151           
  Misses         17       17           
  Partials        2        2           

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