refactor(lint): added new lints and dcm

[tsinis]

Description

Massive refactoring related to the DCM and regular lints also covers some tech-dept topics.

Type of Change

• ✨ New feature (non-breaking change which adds functionality)
• 🛠️ Bug fix (non-breaking change which fixes an issue)
• ❌ Breaking change (fix or feature that would cause existing functionality to change)
• 🧹 Code refactor
• 🧪 Tests
• 📝 Documentation
• ⚙️ CI/CD or GitHub Workflow configuration change
• 📦 Dependencies update

Checks

Please look at the following checklist to ensure that your PR can be accepted quickly:

• Data come from open-source resources with MIT License (if presented).
• New code is documented and the data source is referenced (if presented).
• Existing tests are up to date with these changes.
• New code is fully tested (if presented).

[codecov]

Codecov Report

Attention: Patch coverage is 99.60784% with 1 line in your changes missing coverage. Please review.

Project coverage is 99.96%. Comparing base (c602622) to head (dd426d5).
Report is 12 commits behind head on main.

Files with missing lines	Patch %	Lines
...countries/lib/src/helpers/functional_platform.dart	93.33%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #228      +/-   ##
==========================================
+ Coverage   99.54%   99.96%   +0.42%     
==========================================
  Files          45      205     +160     
  Lines        1106    16585   +15479     
==========================================
+ Hits         1101    16580   +15479     
  Misses          5        5              

Flag	Coverage Δ
sealed_countries	100.00% <100.00%> (?)
sealed_currencies	100.00% <100.00%> (?)
sealed_languages	100.00% <100.00%> (?)
world_countries	99.64% <98.76%> (+0.09%)	⬆️
world_flags	99.99% <ø> (?)

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[tsinis]

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[tsinis]

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