reraise external cancellations

Author: pgrayy

src/strands/experimental/bidi/agent/agent.py

@@ -399,9 +399,14 @@ async def run_outputs(inputs_task: asyncio.Task) -> None:
                 inputs_task.cancel()
                 outputs_task.cancel()
                 await asyncio.gather(inputs_task, outputs_task, return_exceptions=True)
+
                 if not isinstance(error, asyncio.CancelledError):
                     raise
 
+                run_task = asyncio.current_task()
+                if run_task and run_task.cancelling() > 0:  # externally cancelled
+                    raise
+
         finally:
             input_stops = [input_.stop for input_ in inputs if isinstance(input_, BidiInput)]
             output_stops = [output.stop for output in outputs if isinstance(output, BidiOutput)]