chore: resolve linting errors and warnings per PSR-12

[agebhardt]

BEGIN_COMMIT_OVERRIDE
style: resolve linting errors and warnings per PSR-12
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What's New?

• Resolves all linting errors and warnings per PSR-12 standard
• Adds phpcs as a dev dependency
• Adds additional composer scripts for executing lint-related scripts

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have manually tested my code thoroughly
• I have added/updated inline documentation for public facing interfaces if relevant
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing integration and unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules