Twine and pkginfo publish releases; neither is used by the setuptools
build backend. Do not require publishing tools for an offline port build.

Index: pyproject.toml
--- pyproject.toml.orig
+++ pyproject.toml
@@ -1,5 +1,5 @@
 [build-system]
-requires = ["setuptools", "wheel", "twine>=6.1.0", "packaging>=24.2", "pkginfo>=1.12.0"]
+requires = ["setuptools", "wheel", "packaging>=24.2"]
 
 [project]
 name = "google-genai"
