Security audit of input handling

Description

Perform a security audit focusing on input validation and file handling.

Areas to Review

• CSV parsing (injection attacks)
• JSON parsing (DoS via nested objects)
• File path handling (traversal attacks)
• Memory allocation limits
• Integer overflow checks

Tasks

• Review all input parsing code
• Add input size limits
• Add path validation
• Run cargo-audit
• Consider fuzz testing

Acceptance Criteria

• No known vulnerabilities
• Input limits documented
• cargo-audit clean