v0.0.31 - Clean public release

- Updated to v0.0.31 with GUI startup warning fix
- Updated jackify-engine for improved compatibility
- Removed development-only files from public repo
- Added LICENSE and CONTRIBUTING.md for professional release
- Professional public repository ready for alpha release

jackify/backend/core/modlist_operations.py

@@ -592,6 +592,7 @@ class ModlistInstallCLI:
         """
         Run the configuration phase: execute the Linux-native Jackify Install Engine.
         """
+        import os
         import subprocess
         import time
         import sys