* feat: add taint analysis engine for data flow security
Implements SSA-based taint analysis to detect security vulnerabilities:
- G701: SQL injection via string concatenation
- G702: Command injection via user input
- G703: Path traversal via user input
- G704: SSRF via user-controlled URLs
- G705: XSS via unescaped user input
- G706: Log injection via user input
Uses golang.org/x/tools for SSA/call graph analysis with CHA.
Zero external dependencies beyond existing gosec imports.
Cosmin Cojocar
Ravi Sastry Kadali