refactor: Replace map with forEach when possible

[samestep]

Description

This PR replaces map with forEach whenever the returned array is ignored. See also: https://dev.to/smeijer/stop-mutating-in-map-reduce-and-foreach-58bf

Checklist

• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new ESLint warnings
• I have reviewed any generated changes to the diagrams/ folder

Open questions

• Is there a way to lint this automatically for the future?

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[codecov]

Codecov Report

Merging #962 (4984a1f) into main (f714bbe) will not change coverage.
The diff coverage is 88.88%.

@@           Coverage Diff           @@
##             main     #962   +/-   ##
=======================================
  Coverage   63.03%   63.03%           
=======================================
  Files          62       62           
  Lines        7947     7947           
  Branches     1851     1851           
=======================================
  Hits         5009     5009           
  Misses       2814     2814           
  Partials      124      124           

Impacted Files	Coverage Δ
packages/core/src/contrib/Functions.ts	13.71% <75.00%> (ø)
packages/core/src/compiler/Domain.ts	86.22% <100.00%> (ø)
packages/core/src/compiler/Style.ts	78.83% <100.00%> (ø)

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