Python: [Bug]: Hosted agent sample reuses a single workflow instance and breaks under parallel requests

[ManniArora]

Description

The Python sample appears to create or reuse a workflow instance in a way that is not safe for concurrent execution:

python/samples/05-end-to-end/hosted_agents/writer_reviewer_agents_in_workflow/main.py

When the hosted agent receives parallel requests, it can attempt to execute the same workflow instance concurrently and fails with:

RuntimeError: Workflow is already running. Concurrent executions are not allowed.

This makes the sample effectively broken for hosted scenarios where parallel requests are expected.

Link
https://github.com/microsoft/agent-framework/blob/main/python/samples/05-end-to-end/hosted_agents/writer_reviewer_agents_in_workflow/main.py#L55

The sample should be safe for parallel requests in a hosted agent scenario.

Instead of reusing a single workflow instance across requests, it should create a fresh workflow per execution, for example:

async def main() -> None:
    client = AzureOpenAIChatClient(credential=AzureCliCredential())
    await from_agent_framework(lambda: create_workflow(client)).run_async()

Code Sample

Error Messages / Stack Traces

Traceback (most recent call last):
  File "/usr/local/lib/python3.12/site-packages/azure/ai/agentserver/agentframework/_agent_framework.py", line 249, in stream_updates
    async for event in streaming_converter.convert(updates):
  File "/usr/local/lib/python3.12/site-packages/azure/ai/agentserver/agentframework/models/agent_framework_output_streaming_converter.py", line 379, in convert
    async for group in chunk_on_change(updates, is_changed):
  File "/usr/local/lib/python3.12/site-packages/azure/ai/agentserver/agentframework/models/utils/async_iter.py", line 39, in chunk_on_change
    async for group in chunk_by_key(source, lambda x: x, key_equal=key_equal):
  File "/usr/local/lib/python3.12/site-packages/azure/ai/agentserver/agentframework/models/utils/async_iter.py", line 69, in chunk_by_key
    pending = await it.__anext__()
              ^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/agent_framework/_workflows/_agent.py", line 203, in run_stream
    async for update in self._run_stream_impl(
  File "/usr/local/lib/python3.12/site-packages/agent_framework/_workflows/_agent.py", line 282, in _run_stream_impl
    async for event in event_stream:
  File "/usr/local/lib/python3.12/site-packages/agent_framework/_workflows/_workflow.py", line 529, in run_stream
    self._ensure_not_running()
  File "/usr/local/lib/python3.12/site-packages/agent_framework/_workflows/_workflow.py", line 234, in _ensure_not_running
    raise RuntimeError("Workflow is already running. Concurrent executions are not allowed.")
RuntimeError: Workflow is already running. Concurrent executions are not allowed.

Package Versions

azure-ai-agentserver-agentframework==1.0.0b14

Python Version

No response

Additional Context

No response