Enhance Security Sniff Coverage

Expand security sniff capabilities and add new security-focused rules based on modern web application vulnerabilities.

Acceptance Criteria:

• Audit existing security sniffs for completeness
• Add SQL injection prevention sniffs
• Add XSS prevention additional patterns
• Create CSRF protection validation sniffs
• Add secure configuration sniffs
• Update security documentation
• Create security-focused examples

Related Files:

• src/ArtisanPackUI/Sniffs/Security/*.php
• docs/sniffs/security-sniffs.md