Add helper functions for KCL execution

[adamchalmers]

No description provided.

[codecov]

Codecov Report

❌ Patch coverage is 0% with 12 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (main@db94750). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
modeling-cmds/src/exec_kcl.rs	0.00%	12 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1264   +/-   ##
=======================================
  Coverage        ?   31.51%           
=======================================
  Files           ?       36           
  Lines           ?     1793           
  Branches        ?        0           
=======================================
  Hits            ?      565           
  Misses          ?     1228           
  Partials        ?        0           

Flag	Coverage Δ
unittests	31.51% <0.00%> (?)

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