Fix Python 3 compatibility and runtime errors

[senpai80085]

Summary

This PR fixes Python 3 compatibility issues in chankro.py that prevent the tool from running on modern systems.

Changes

• Converted Python 2 print statements to Python 3 syntax
• Fixed inconsistent indentation (tabs vs spaces)
• Replaced bare except statements with IOError handling
• Corrected bytes vs string handling for base64-encoded data
• Preserved original exploit logic and CLI behavior

Testing

• Python 3.11
• Windows 11
• Verified with:
  • python3 -m py_compile chankro.py
  • python3 chankro.py --help