Fix static project version and use a Python 3.9-compatible hatchling

The [project] version in pyproject.toml is static ([tool.hatch.version]
is only consulted when version is declared dynamic), so bumping
version.py alone left the packaging metadata and uv.lock at 3.4.2.
Set the static version to 3.5.0 to match.

Pin hatchling to 1.27.0 instead of 1.31.0: 1.28+ requires Python 3.10,
while this package's requires-python still includes 3.9, so the newer
pin would break sdist builds on 3.9.

Addresses PR#103 review findings.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Signed-off-by: lelia <2418071+lelia@users.noreply.github.com>

Author: lelia

pyproject.toml

@@ -1,10 +1,12 @@
 [build-system]
-requires = ["hatchling==1.31.0"]
+# 1.27.0 is the newest hatchling that supports Python 3.9, which this
+# package's requires-python still includes.
+requires = ["hatchling==1.27.0"]
 build-backend = "hatchling.build"
 
 [project]
 name = "socketdev"
-version = "3.4.2"
+version = "3.5.0"
 requires-python = ">= 3.9"
 dependencies = [
     'requests>=2.32.5,<3',