fix(a2a): set final=True for error TaskStatusUpdateEvent in event_converter

[kuishou68]

Closes #5388

Problem

In _create_error_status_event inside src/google/adk/a2a/converters/event_converter.py, the TaskStatusUpdateEvent for a failed task is incorrectly created with final=False:

return TaskStatusUpdateEvent(
    ...
    status=TaskStatus(state=TaskState.failed, ...),
    final=False,  # BUG: should be True
)

A failed state is terminal — no further events will follow, so final must be True. Consumers that check this flag will otherwise wait indefinitely or mishandle the error.

Fix

Change final=False → final=True in _create_error_status_event.

The equivalent code in from_adk_event.py already uses final=True correctly (line 154), so this change makes event_converter.py consistent.

Testing

Existing unit tests for error event conversion should be updated/added to assert final=True.

Signed-off-by: Cocoon-Break 54054995+kuishou68@users.noreply.github.com

[adk-bot]

Response from ADK Triaging Agent

Hello @kuishou68, thank you for your contribution!

Your PR description is very clear and it's great that you've included an associated issue and a testing plan.

As per our contribution guidelines, could you please also include a summary of the passed pytest results to verify the fix? This will help speed up the review process.

Thanks!

[rohityan]

Hi @kuishou68, Thank you for your contribution! We appreciate you taking the time to submit this pull request. Your PR has been received by the team and is currently under review. We will provide feedback as soon as we have an update to share.

[rohityan]

Hi @sasha-gitg , can you please review this.