docs: improve Arcade Games contribution guide formatting

[SEBINSHASAMEERSHA]

Description

This pull request improves the formatting and readability of the root CONTRIBUTING.md guide for the Arcade Games repository.

The changes include:

• improving the opening description
• adding a proper Table of Contents heading
• removing duplicated Window Size guidance
• improving the file-path example formatting and wording
• preserving the existing technical requirements

This work contributes to the Planner task concerning Arcade Games documentation that does not fully follow the project’s Markdown guidelines.

Fixes # (no linked GitHub issue)

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 not to work as expected)
• Documentation (update or new)

How Has This Been Tested?

The updated CONTRIBUTING.md file was reviewed in VS Code using the Markdown preview.

The following were checked:

• headings render correctly
• the Table of Contents remains readable
• code blocks are unaffected
• no links or images were changed
• the technical meaning of the contribution requirements remains unchanged

Testing Checklist

• Tested in latest Chrome
• Tested in latest Safari
• Tested in latest Firefox

Browser testing is not applicable because this pull request only changes repository Markdown documentation.

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own changes
• I have commented my code in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have requested a review from a project team member

[jankiluitel]

Looks good to me. The documentation is now clearer and more concise, with improved wording and formatting throughout. The updated guidance is easier to follow, and the examples improve readability for new contributors.

I have one minor suggestion for a future improvement: consider updating the Table of Contents so it reflects all of the current section headings. This is a non-blocking documentation enhancement.

Approved.