feat(Promotion): Make ordered lanes an array

[tvdeyen]

Summary

We always use this method as an array anyway (ignoring the index value in all cases).

Let's remove the cognitive overhead to keep in mind that this is a sorted hash and make it more natural to use.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.34%. Comparing base (2d1fcff) to head (be0c164).
⚠️ Report is 6 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6345   +/-   ##
=======================================
  Coverage   89.34%   89.34%           
=======================================
  Files         961      961           
  Lines       20165    20165           
=======================================
  Hits        18016    18016           
  Misses       2149     2149           

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[mamhoff]

Thank you. Always good to remove cognitive overhead from this code base.