* Improve code style and PSR-12 compliance
- refactored code formatting to adhere to PSR-12 guidelines
- standardized coding conventions across the codebase
- added missing framework files and reverted markup changes
- reformatted arrays for enhanced readability
- updated language files for consistent styling and clarity
- minor miscellaneous improvements
- Added missing PHPdocs
- Corrected Syntax
- Added noinspection parameters to PHPdoc for AJAX called functions
- Added missing function return types
- Added missing parameter types
- Added public keyword to functions without visibility modifier
- Corrected incorrectly formatted PHPdocs
- Added public to constants and functions missing a visibility keyword
- Replaced TRUE/FALSE constants with true/false keywords
- Replaced NULL constant with null keyword
- Replaced `<?php echo` in views with shortened `<?=`
- Added missing variable declaration
- Added missing function return type in declaration
- replaced `== true`, `== false`, `=== true` and `=== false` in if statements with simplified forms
