docs: professional repository documentation updates

[GhostwheeI]

This PR enhances the repository's documentation to make it more professional and ready for an official release.

Changes included:

• README.md: Added standard badges (Version, Platform, PowerShell version, License) and a Table of Contents. Updated introductory text.
• CONTRIBUTING.md: Added a standard guide for reporting bugs and creating pull requests.
• SECURITY.md: Added a standard security policy outlining supported versions and vulnerability reporting procedures.

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PR created automatically by Jules for task 5259573337635203932 started by @GhostwheeI

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