ci: improve lint

[tilucasoli]

Description

This pull request introduces several updates across the codebase, focusing on enhancing code quality, refining imports, and updating dependencies. Key changes include adding Dart Code Metrics configurations, updating imports for consistency, and removing unused code.

[docs-page]

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docs.page/btwld/remix~3

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[github-actions]

LCOV of commit 0f99cdf during Flutter CI #11

	(use "lcov --ignore-errors deprecated,deprecated ..." to suppress this warning)
Reading tracefile /tmp/__zgosalvez_github-actions-report-lcov/lcov.info.
Summary coverage rate:
  source files: 88
  lines.......: 57.1% (1916 of 3354 lines)
  functions...: no data found
  branches....: no data found
Message summary:
  1 warning message:
    deprecated: 1

Files changed coverage rate:
  	(use "lcov --ignore-errors deprecated,deprecated ..." to suppress this warning)
                                                                         |Lines       |Functions  |Branches    
  Filename                                                               |Rate     Num|Rate    Num|Rate     Num
  lib/src/components/content_presentation/accordion/accordion.dart       | 9.1%     11|    -     0|    -      0
  lib/src/components/content_presentation/chip/chip.dart                 |25.0%      4|    -     0|    -      0
  lib/src/components/form/checkbox/checkbox.dart                         |25.0%      4|    -     0|    -      0
  lib/src/components/form/radio/radio.dart                               |25.0%      4|    -     0|    -      0
  lib/src/components/form/select/select.dart                             |10.7%     28|    -     0|    -      0
  lib/src/components/form/select/select_widget.dart                      |97.1%    138|    -     0|    -      0
  lib/src/components/form/switch/switch.dart                             |25.0%      4|    -     0|    -      0
  lib/src/components/form/textfield/textfield_widget.dart                |95.8%    120|    -     0|    -      0
  lib/src/components/overlay/tooltip.dart                                |25.0%      4|    -     0|    -      0
  lib/src/core/style_scope.dart                                          | 100%      5|    -     0|    -      0