refactor(toolkit): various test organization improvements

[mrgrain]

Mostly in prepartion of the upcoming file move to reduce noise.

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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.98%. Comparing base (38d6443) to head (b84208a).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #321      +/-   ##
==========================================
+ Coverage   85.10%   86.98%   +1.88%     
==========================================
  Files         223      218       -5     
  Lines       36990    35583    -1407     
  Branches     4474     4372     -102     
==========================================
- Hits        31480    30953     -527     
+ Misses       5413     4532     -881     
- Partials       97       98       +1     

Flag	Coverage Δ
suite.unit	86.98% <ø> (+1.88%)	⬆️

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