build: add Codex package builder

scripts/build_codex_package.py

@@ -0,0 +1,16 @@
+#!/usr/bin/env python3
+"""Build a canonical Codex package directory and optional archive."""
+
+from pathlib import Path
+import sys
+
+
+# Some developer environments set PYTHONSAFEPATH=1, which prevents Python from
+# adding the script directory to sys.path. Add it explicitly so the local helper
+# package remains importable when this executable is launched from any cwd.
+sys.path.insert(0, str(Path(__file__).resolve().parent))
+
+from codex_package.cli import main
+
+if __name__ == "__main__":
+    raise SystemExit(main())