feat: generate stack definitions for refactoring

[otaviomacedo]

Having a list of deployed stacks, and the mappings (either computed or user provided), we have to generate a list of stack definitions to be sent to the createStackRefactor API.

The function generateStackDefinitions is not yet used anywhere, other than unit tests. Future PRs will use it to make the API call.

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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.17%. Comparing base (40a3137) to head (2e39730).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #477   +/-   ##
=======================================
  Coverage   79.17%   79.17%           
=======================================
  Files          54       54           
  Lines        6914     6914           
  Branches      774      774           
=======================================
  Hits         5474     5474           
  Misses       1422     1422           
  Partials       18       18           

Flag	Coverage Δ
suite.unit	79.17% <ø> (ø)

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