refactor(toolkit-lib): move code from tmp-toolkit-helpers

[mrgrain]

Move all code and tests from tmp-toolkit-helpers to toolkit-lib. Remove the now empty package. Made necessary changes to imports, config and tests. No functional code changes!

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license

[github-actions]

Total lines changed 2510 is greater than 1000. Please consider breaking this PR down.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 80.94%. Comparing base (f12ec97) to head (45ea1c7).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #424      +/-   ##
==========================================
+ Coverage   80.27%   80.94%   +0.66%     
==========================================
  Files          66       65       -1     
  Lines        6894     6900       +6     
  Branches      790      797       +7     
==========================================
+ Hits         5534     5585      +51     
+ Misses       1340     1295      -45     
  Partials       20       20              

Flag	Coverage Δ
suite.unit	80.94% <100.00%> (+0.66%)	⬆️

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