Update CONTRIBUTING.md with contribution guidelines

This document outlines the guidelines for contributing to the development of Shipping Rates and Calculations, including code style, documentation, testing, issue tracking, and code review.

Author: 1DeliDolu

CONTRIBUTING.md

@@ -1 +1,20 @@
-All contributions, bug reports, bug fixes, documentation improvements, enhancements, and ideas are welcome.
+Contribution guidelines
+Welcome Contributors!
+Thank you for considering contributing to the centralized repository. This document outlines the guidelines for contributing to the development of Shipping Rates and Calculations.
+
+Code style
+Please follow the coding style and conventions used in the existing codebase. This helps maintain consistency across the project.
+
+Documentation
+Ensure that your contributions are well-documented. Include comments in your code where necessary and provide a clear and concise description of your changes in the pull request.
+
+Testing
+Before submitting a pull request, make sure your changes have been tested thoroughly. Include relevant test cases and ensure that existing tests pass.
+
+Issue tracker
+Check the issue tracker for any open issues or feature requests. If you're working on something, please comment on the issue to let others know.
+
+Code review
+All contributions will go through a code review process. Be open to feedback and be willing to make changes if necessary. Code reviews help maintain code quality and consistency.
+
+Thank you for your contribution!