feat(security): Implement file upload security (#1753)

[AIFlowML]

Security Enhancements for File Upload System solve #1753

Overview

This PR implements comprehensive security measures for the file upload system in plugin-0g. The changes focus on preventing unauthorized access, malicious file uploads, and potential security vulnerabilities.

Key Improvements

1. FileSecurityValidator

• Implemented robust file type validation
• Added size restrictions with configurable limits
• Enhanced path security to prevent directory traversal
• Improved error handling and logging

2. Error Handling

• Added structured logging with elizaLogger
• Implemented detailed error messages
• Enhanced security event monitoring
• Added upload metrics tracking

Implementation Details

Security Validations

1. File Type Validation

   • Early validation before processing
   • Configurable allowed extensions
   • Prevention of sensitive file uploads

2. Size Restrictions

   • Default 10MB limit
   • Configurable via environment
   • DoS attack prevention

3. Path Security

   • Directory traversal prevention
   • Upload directory restrictions
   • Path sanitization

Monitoring

1. Security Events
   • Structured event logging
   • Severity classification
   • Detailed context capture

Security Checklist

• File type validation
• Size restrictions
• Path security
• Error handling
• Logging implementation
• Test coverage
• Documentation

Documentation

• Added security guide in README.md
• Updated error message documentation
• Added configuration guide

Testing Results

• All tests passing (8/8)
• No linter errors
• Security validations verified
• Error handling confirmed