Revise readmes for patchstack faq

[jeffpaul]

Updated the readme file to reflect the latest version and features of ClassifAI.

Description of the Change

This pull request updates the plugin documentation to improve clarity, organization, and security reporting instructions. The most significant changes are the addition of a security bug reporting section and restructuring of the readme.txt file using standard WordPress formatting.

Documentation improvements:

• Added a new section to both README.md and readme.txt explaining how to report security bugs via the Patchstack Vulnerability Disclosure Program, including a direct link and description of the process. [1] [2]
• Introduced a "Frequently Asked Questions" section in readme.txt to house the new security reporting instructions, making it easier for users to find important information.

Readme formatting and structure:

• Updated headings in readme.txt from Markdown-style (e.g., **Features**) to WordPress standard formatting (e.g., == Features ==, == Requirements ==) for improved compatibility and readability. [1] [2]
• Added a blank line after the last changelog entry in readme.txt to maintain consistent formatting.

How to test the Change

Changelog Entry

Developer - Add Patchstack security-reporting FAQ.

Credits

Props @jeffpaul.

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly.
• I have added Critical Flows, Test Cases, and/or End-to-End Tests to cover my change.
• All new and existing tests pass.