Refactor localization files formatting and code style

Cleaned up and standardized formatting across localization files:
- Improved multiline string formatting
- Aligned code style with consistent indentation
- Removed unnecessary line breaks
- Simplified code structure in generated localization files

Bump package version to 2.1.6-pre.2

- Updated CHANGELOG.md with new version
- Incremented package version in pubspec.yaml

Add version extraction script to GitHub workflows and bump package ve…

…rsion

- Introduced a Dart script to dynamically extract version from pubspec.yaml
- Updated git_package_release.yml and pub_package_publish.yml to use dynamic version extraction
- Bumped l10n_mapper_generator package version to 2.1.6-pre.1
- Updated CHANGELOG.md with new version details

Updated package release version

Updated package release version

Updated package release version to 2.1.3.

Updated package release version to 2.1.2.

Updated release version and readme.

[FEATURE] Change generated mapper extension to `.mapper.dart` (#23)

## Description

PS. This fix is aimed to resolve this
[feature-request](#22)

## Please check the following boxes

<!--- Put an `X` in all the boxes that apply: -->

- [x] Pull Request title is consistent with the implemented feature, fix
etc.
- [x] I have followed proper descriptive code style and conventions
- [x] The code is self-documenting and has no unnecessary comments. I
named the functions and variables to clearly describe their purpose.
- [ ] I have added Unit Tests and coverage is 70%+
- [x] I have tested and verified this implementation and it works as
expected

[FIX] Updated package dependencies to resolve analysis issues. (#21)

## Description

[Updated package dependencies to resolve analysis
issues](fb853d3)

## Please check the following boxes

<!--- Put an `X` in all the boxes that apply: -->

- [x] Pull Request title is consistent with the implemented feature, fix
etc.
- [x] I have followed proper descriptive code style and conventions
- [x] The code is self-documenting and has no unnecessary comments. I
named the functions and variables to clearly describe their purpose.
- [ ] I have added Unit Tests and coverage is 70%+
- [x] I have tested and verified this implementation and it works as
expected