fix(grpc): Add extensions to Artifact converters. (#523)

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Author: 3 people

src/a2a/utils/proto_utils.py

@@ -57,7 +57,7 @@ def make_dict_serializable(value: Any) -> Any:
  Returns:
  A serializable value.
  """
- if isinstance(value, (str, int, float, bool)) or value is None:
+ if isinstance(value, str | int | float | bool) or value is None:
  return value
  if isinstance(value, dict):
  return {k: make_dict_serializable(v) for k, v in value.items()}
@@ -140,6 +140,7 @@ def message(cls, message: types.Message | None) -> a2a_pb2.Message | None:
  task_id=message.task_id or '',
  role=cls.role(message.role),
  metadata=cls.metadata(message.metadata),
+ extensions=message.extensions or [],
  )
 
  @classmethod
@@ -239,6 +240,7 @@ def artifact(cls, artifact: types.Artifact) -> a2a_pb2.Artifact:
  metadata=cls.metadata(artifact.metadata),
  name=artifact.name,
  parts=[cls.part(p) for p in artifact.parts],
+ extensions=artifact.extensions or [],
  )
 
  @classmethod
@@ -695,6 +697,7 @@ def artifact(cls, artifact: a2a_pb2.Artifact) -> types.Artifact:
  metadata=cls.metadata(artifact.metadata),
  name=artifact.name,
  parts=[cls.part(p) for p in artifact.parts],
+ extensions=artifact.extensions or None,
  )
 
  @classmethod