* fix(deps): declare setuptools in dev extra for packaging tests
tests/test_packaging_metadata.py imports `from setuptools import
find_packages` at module scope to validate package discovery against
the live tree. setuptools was being picked up ambiently from the CI
runner image, but recent ubuntu-latest images no longer ship it in the
test venv, so collection fails with ModuleNotFoundError on every PR.
Declare setuptools==82.0.1 in the dev optional-dependencies so `.[all,dev]`
installs it explicitly rather than relying on the runner environment.
* test(packaging): skip packaging-metadata tests when setuptools absent
Belt-and-suspenders alongside declaring setuptools in [dev]: guard the
module-level `from setuptools import find_packages` with
pytest.importorskip so a runner missing setuptools SKIPS these checks
instead of erroring out collection for the entire test shard.
* chore(deps): sync uv.lock for setuptools dev dependency
f9daa4a41d