build: emit core metadata 2.4 until twine accepts 2.5

hatchling 1.32.0 (2026-08-11) bumped the default core metadata version
to 2.5, which the twine run by build-and-inspect-python-package rejects
('InvalidDistribution: 2.5 is not a valid metadata version').  Nobody
noticed because build-and-inspect needs the test job, which has been
red since mid-July (see previous commit).  Verified locally: with this
setting both the wheel and sdist emit Metadata-Version 2.4 and pass
'twine check --strict'.

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

Author: larsoner

pyproject.toml

@@ -5,6 +5,15 @@ build-backend = "hatchling.build"
 [tool.hatch.version]
 source = "vcs"
 
+# hatchling 1.32 emits core metadata 2.5 by default, which twine (as run by
+# build-and-inspect-python-package) rejects.  TODO: remove once twine there
+# accepts metadata 2.5.
+[tool.hatch.build.targets.sdist]
+core-metadata-version = "2.4"
+
+[tool.hatch.build.targets.wheel]
+core-metadata-version = "2.4"
+
 # https://peps.python.org/pep-0621/
 [project]
 name = "magicgui"