Implement real virus scanning service for file uploads

[davedumto]

Problem

Virus scanning is placeholder only, creating security risk:

// TODO: Integrate with a real virus scanning service

This allows:

• Malicious file uploads
• Security vulnerabilities
• Potential system compromise
• No file validation

Impact

• Security vulnerabilities
• Potential system compromise
• No protection against malicious files
• Compliance issues

Solution

Integrate with real virus scanning service:

• Implement ClamAV or similar service
• Add file validation and scanning
• Block malicious file uploads
• Add security logging

Implementation Options

• ClamAV integration
• VirusTotal API integration
• Cloud-based virus scanning service
• Custom file validation rules

Acceptance Criteria

• Implement real virus scanning service
• Block malicious file uploads
• Add security logging
• File validation rules
• Integration with existing upload flow
• Error handling for scanning failures