Skip editable package in pip-audit; require setuptools>=83.0.0

pip-audit can't look up the local editable "gallery" package on PyPI,
so skip it explicitly. Also bump the setuptools build requirement to
pull in recent security fixes.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

pyproject.toml

@@ -1,5 +1,5 @@
 [build-system]
-requires = ["setuptools>=65.0", "wheel"]
+requires = ["setuptools>=83.0.0", "wheel"]
 build-backend = "setuptools.build_meta"
 
 [project]