fix: Update Proto Version to 6.31.1 for compatibility

Fixes #173

Author: holtskinner

buf.gen.yaml

@@ -19,12 +19,12 @@ managed:
 plugins:
   # Generate python protobuf related code
   # Generates *_pb2.py files, one for each .proto
-  - remote: buf.build/protocolbuffers/python:v29.3
+  - remote: buf.build/protocolbuffers/python:v31.1
     out: src/a2a/grpc
   # Generate python service code.
   # Generates *_pb2_grpc.py
   - remote: buf.build/grpc/python
     out: src/a2a/grpc
   # Generates *_pb2.pyi files.
-  - remote: buf.build/protocolbuffers/pyi:v29.3
+  - remote: buf.build/protocolbuffers/pyi:v31.1
     out: src/a2a/grpc

src/a2a/grpc/a2a_pb2.py

@@ -1,3 +1,5 @@
+import datetime
+
 from google.api import annotations_pb2 as _annotations_pb2
 from google.api import client_pb2 as _client_pb2
 from google.api import field_behavior_pb2 as _field_behavior_pb2
@@ -7,7 +9,8 @@ from google.protobuf.internal import containers as _containers
 from google.protobuf.internal import enum_type_wrapper as _enum_type_wrapper
 from google.protobuf import descriptor as _descriptor
 from google.protobuf import message as _message
-from typing import ClassVar as _ClassVar, Iterable as _Iterable, Mapping as _Mapping, Optional as _Optional, Union as _Union
+from collections.abc import Iterable as _Iterable, Mapping as _Mapping
+from typing import ClassVar as _ClassVar, Optional as _Optional, Union as _Union
 
 DESCRIPTOR: _descriptor.FileDescriptor
 
@@ -77,7 +80,7 @@ class TaskStatus(_message.Message):
     state: TaskState
     update: Message
     timestamp: _timestamp_pb2.Timestamp
-    def __init__(self, state: _Optional[_Union[TaskState, str]] = ..., update: _Optional[_Union[Message, _Mapping]] = ..., timestamp: _Optional[_Union[_timestamp_pb2.Timestamp, _Mapping]] = ...) -> None: ...
+    def __init__(self, state: _Optional[_Union[TaskState, str]] = ..., update: _Optional[_Union[Message, _Mapping]] = ..., timestamp: _Optional[_Union[datetime.datetime, _timestamp_pb2.Timestamp, _Mapping]] = ...) -> None: ...
 
 class Part(_message.Message):
     __slots__ = ("text", "file", "data")

src/a2a/grpc/a2a_pb2.pyi

@@ -2,7 +2,7 @@
 """Client and server classes corresponding to protobuf-defined services."""
 import grpc
 
-from . import a2a_pb2 as a2a__pb2
+import a2a_pb2 as a2a__pb2
 
 
 class A2AServiceStub(object):