Declare the version dynamic so version.py is the single source of truth

Per review on PR#103: with dynamic = ["version"], hatchling reads
socketdev/version.py (the file version-check.yml already validates),
so packaging metadata can never drift from the checked version again.

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

Author: lelia

pyproject.toml

@@ -6,7 +6,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "socketdev"
-version = "3.5.0"
+dynamic = ["version"]
 requires-python = ">= 3.9"
 dependencies = [
     'requests>=2.32.5,<3',