Use versioningit's git-archive method, to support zip archive installs

https://versioningit.readthedocs.io/en/stable/configuration.html#git-archive

Author: amotl

.gitattributes

@@ -0,0 +1 @@
+pyproject.toml export-subst

pyproject.toml

@@ -84,6 +84,7 @@ dependencies = [
   "backports.zoneinfo<1; python_version<'3.9'",
   "crate>=2,<3",
   "geojson<4,>=2.5",
+  "importlib-metadata; python_version<'3.8'",
   "importlib-resources; python_version<'3.9'",
   "sqlalchemy<2.1,>=1",
   "verlib2<0.3",
@@ -252,8 +253,9 @@ non_interactive = true
 # enable_recursive_aliases = true
 
 [tool.versioningit.vcs]
-method = "git"
+method = "git-archive"
 default-tag = "0.0.0"
+describe-subst = "$Format:%(describe:tags)$"
 
 # ===================
 # Tasks configuration

src/sqlalchemy_cratedb/__init__.py

@@ -52,7 +52,22 @@
     monkeypatch_add_exec_driver_sql()
 
 
+try:
+    from importlib.metadata import PackageNotFoundError, version
+except (ImportError, ModuleNotFoundError):  # pragma:nocover
+    from importlib_metadata import (  # type: ignore[assignment,no-redef,unused-ignore]
+        PackageNotFoundError,
+        version,
+    )
+
+try:
+    __version__ = version("sqlalchemy-cratedb")
+except PackageNotFoundError:  # pragma: no cover
+    __version__ = "unknown"
+
+
 __all__ = [
+    __version__,
     dialect,
     FloatVector,
     Geopoint,