fix: version test compat with Python 3.10 (no tomllib)

Use regex to parse version from pyproject.toml instead of tomllib
which is only available in Python 3.11+.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: NMitchem

tests/test_version.py

@@ -1,13 +1,14 @@
 def test_version_matches_pyproject():
     """Version in __init__.py must match pyproject.toml."""
-    import tomllib
+    import re
     from pathlib import Path
     from skillscan import __version__
 
     pyproject = Path(__file__).parent.parent / "pyproject.toml"
-    with open(pyproject, "rb") as f:
-        meta = tomllib.load(f)
-    assert __version__ == meta["project"]["version"]
+    text = pyproject.read_text()
+    match = re.search(r'^version\s*=\s*"([^"]+)"', text, re.MULTILINE)
+    assert match, "Could not find version in pyproject.toml"
+    assert __version__ == match.group(1)
 
 
 def test_sarif_fallback_version():