Fix __version__ drift by deriving from package metadata

src/maine_forms_engine/__init__.py

@@ -9,4 +9,11 @@
 NOT legal advice — see DISCLAIMER.md.
 """
 
-__version__ = "0.5.0"
+from importlib.metadata import PackageNotFoundError, version
+
+try:
+    # Derive from installed package metadata so it can never drift from pyproject.
+    __version__ = version("maine-forms-engine")
+except PackageNotFoundError:
+    # Fallback for a source tree that isn't installed; keep in sync with pyproject.
+    __version__ = "0.6.0"

tests/test_version.py

@@ -0,0 +1,11 @@
+"""The package's ``__version__`` must match the installed distribution
+metadata (which is built from pyproject's ``version``), so a check keyed on
+``maine_forms_engine.__version__`` can never read a stale, hand-edited value.
+"""
+from importlib.metadata import version
+
+import maine_forms_engine
+
+
+def test_version_matches_installed_metadata():
+    assert maine_forms_engine.__version__ == version("maine-forms-engine")