chore: Adding traceback logging to inference step of eval

Right now the failure eats up the traceback information and there is no clear way for the developer to know what went wrong. Adding this traceback info could give them the needed debugging information.

PiperOrigin-RevId: 823179833

Author: ankursharmas

src/google/adk/evaluation/local_eval_service.py

@@ -432,9 +432,10 @@ async def _perform_inference_sigle_eval_item(
       # We intentionally catch the Exception as we don't failures to affect
       # other inferences.
       logger.error(
-          'Inference failed for eval case `%s` with error %s',
+          'Inference failed for eval case `%s` with error %s.',
           eval_case.eval_id,
           e,
+          exc_info=True,
       )
       inference_result.status = InferenceStatus.FAILURE
       inference_result.error_message = str(e)