Add CLI Flag for --forced-separate

[hirak99]

Implements #2366

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.25%. Comparing base (aade4b3) to head (0d7d865).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2367   +/-   ##
=======================================
  Coverage   99.25%   99.25%           
=======================================
  Files          40       40           
  Lines        3079     3080    +1     
  Branches      671      671           
=======================================
+ Hits         3056     3057    +1     
  Misses         13       13           
  Partials       10       10           

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