feat: add many to many support in CrudFactory (#65)

src/fastapi_toolsets/crud/__init__.py

@@ -1,7 +1,7 @@
 """Generic async CRUD operations for SQLAlchemy models."""
 
 from ..exceptions import NoSearchableFieldsError
-from .factory import CrudFactory
+from .factory import CrudFactory, JoinType, M2MFieldType
 from .search import (
     SearchConfig,
     get_searchable_fields,
@@ -10,6 +10,8 @@ from .search import (
 __all__ = [
     "CrudFactory",
     "get_searchable_fields",
+    "JoinType",
+    "M2MFieldType",
     "NoSearchableFieldsError",
     "SearchConfig",
 ]