Add description field support to InfrahubPythonTransformConfig

Add an optional `description` field to `InfrahubPythonTransformConfig`
to achieve parity with `InfrahubJinja2TransformConfig`. This allows users
to set descriptions for Python transforms in `.infrahub.yml`.

Closes opsmill/infrahub#6382

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: minitriga

infrahub_sdk/schema/repository.py

@@ -128,6 +128,7 @@ class InfrahubPythonTransformConfig(InfrahubRepositoryConfigElement):
         default=False,
         description="Decide if the transform should convert the result of the GraphQL query to SDK InfrahubNode objects.",
     )
+    description: str | None = Field(default=None, description="Description for this transform")
 
     def load_class(self, import_root: str | None = None, relative_path: str | None = None) -> type[InfrahubTransform]:
         module = import_module(module_path=self.file_path, import_root=import_root, relative_path=relative_path)

tests/unit/sdk/test_schema.py

@@ -341,6 +341,27 @@ async def test_infrahub_repository_config_dups() -> None:
     assert "Found multiples element with the same names: ['check01', 'check02']" in str(exc.value)
 
 
+async def test_python_transform_config_description() -> None:
+    """Verify InfrahubPythonTransformConfig supports an optional description field."""
+    # With description
+    config_with_desc = InfrahubPythonTransformConfig(
+        name="my_transform", file_path="transforms/my.py", class_name="MyTransform", description="A useful transform"
+    )
+    assert config_with_desc.description == "A useful transform"
+
+    # Without description (default None)
+    config_without_desc = InfrahubPythonTransformConfig(
+        name="my_transform", file_path="transforms/my.py", class_name="MyTransform"
+    )
+    assert config_without_desc.description is None
+
+    # Explicit None
+    config_explicit_none = InfrahubPythonTransformConfig(
+        name="my_transform", file_path="transforms/my.py", class_name="MyTransform", description=None
+    )
+    assert config_explicit_none.description is None
+
+
 @mock.patch(
     "infrahub_sdk.ctl.schema.get_node",
     return_value={