Add ClawSec and ClawSearch - Security audit and safe skill discovery

[huacheng]

Summary

Adding ClawSec and ClawSearch under a new Security & Auditing subsection within Extensions & Integrations.

• ClawSec — 5-tier security audit for AI agent skills with Trust Score system. Detects prompt injection, data exfiltration, and malicious patterns.
• ClawSearch — Safe skill discovery platform for Claude and other AI agents. Curated registry of audited, trusted skills.

Entry Added

• Section: Extensions & Integrations > Security & Auditing (new subsection)
• Format: Matches existing entry format (- [Name](url) - Description.)