Add kd-screen-guard to Security section

[KhvichaDev]

Added kd-screen-guard library to the Security section.

Checklist:

• I've read and understood Contributing Guidelines.
• I've added the new resource at the end of its section.
• This resource is out there for a while, and actively maintained.
• This resource is popular enough and has at least a few hundred stars on GitHub.

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kd-screen-guard is a standalone, zero-dependency, tamper-proof lock screen library for web applications:

• WebAuthn Biometrics (Touch ID, Face ID, Windows Hello)
• WebRTC Intruder Snapshot capture
• Off-main-thread Web Worker PBKDF2 cryptography
• Self-healing Anti-Tamper DOM protection
• Framework-agnostic with native React & Vue 3 hooks

GitHub: https://github.com/KhvichaDev/kd-screen-guard
NPM: https://www.npmjs.com/package/kd-screen-guard