Complete Security Analysis Enhancement (Issue #11)

✨ Enhanced SecurityAnalyzer with comprehensive vulnerability detection:

🔍 **New Vulnerability Types:**
- XSS detection (innerHTML, document.write, eval)
- CSRF protection analysis (forms, AJAX requests)
- Enhanced authentication patterns (hardcoded API keys)
- Additional crypto weaknesses (weak RNG)
- Data exposure patterns (sensitive URLs)
- Unsafe deserialization detection

📊 **CVSS v3.1 Scoring System:**
- Base score calculation with context awareness
- Environmental factors (test vs production files)
- Severity classification (Low/Medium/High/Critical)
- Confidence scoring for each finding

🏷️ **OWASP Top 10 Mapping:**
- Complete mapping to OWASP 2021 categories
- Enhanced reporting with security standards compliance
- Actionable remediation guidance with emojis

🔧 **MCP Tool Integration:**
- Fully functional analyze_security tool
- Repository-wide file scanning (20+ file types)
- Real-time vulnerability analysis with line numbers
- Comprehensive security reporting with metadata

🎯 **Key Features:**
- Supports injection, XSS, CSRF, auth, crypto, data exposure
- Context-aware severity adjustments
- High-confidence vulnerability detection
- Performance optimized for large codebases
- Detailed location information (file, line, position)

✅ **Testing & Validation:**
- All existing tests pass
- Enhanced security test coverage
- Added security-test.js with vulnerability examples
- Comprehensive error handling and edge cases

Closes #11

Author: milliondreams