`python -m asyncio ps` fails if any task name is longer than 255 characters

Bug report

Bug description:

One task name longer than 255 characters makes python -m asyncio ps fail for the whole process. The length limit is treated as a validity check instead of a cap.

Repro:

  import asyncio
  import os
  from _remote_debugging import RemoteUnwinder

  async def main():
      asyncio.create_task(asyncio.sleep(10), name='x' * 256)
      await asyncio.sleep(0)
      print(RemoteUnwinder(os.getpid()).get_all_awaited_by())

  asyncio.run(main())

Actually:

  Traceback (most recent call last):
    File "/Users/timofeiivankov/cpython/repro.py", line 10, in <module>
      asyncio.run(main())
      ~~~~~~~~~~~^^^^^^^^
    File "/Users/timofeiivankov/cpython/Lib/asyncio/runners.py", line 205, in run
      return runner.run(main)
             ~~~~~~~~~~^^^^^^
    File "/Users/timofeiivankov/cpython/Lib/asyncio/runners.py", line 128, in run
      return self._loop.run_until_complete(task)
             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^
    File "/Users/timofeiivankov/cpython/Lib/asyncio/base_events.py", line 725, in run_until_complete
      return future.result()
             ~~~~~~~~~~~~~^^
    File "/Users/timofeiivankov/cpython/repro.py", line 8, in main
      print(RemoteUnwinder(os.getpid()).get_all_awaited_by())
            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^
  RuntimeError: Invalid string length (256) at 0x101493800

Expected: the call returns and the long name comes back truncated:

[AwaitedInfo(thread_id=21170325, awaited_by=[
  TaskInfo(task_id=4312485712, task_name='Task-1', ...),
  TaskInfo(task_id=4312485232, task_name='xxx…' (truncated to 255), ...)])]

Proposed fix: Truncate to the limit instead of raising in object_reading.c

I have a fix ready for that

CPython versions tested on:

CPython main branch

Operating systems tested on:

macOS

Linked PRs

• gh-157790

Bắt đầu trong object_reading.c và tái hiện lỗi bằng ví dụ tên task của asyncio được cung cấp, sử dụng python -m asyncio ps hoặc lệnh gọi RemoteUnwinder được示. Hoàn thành khi lệnh gọi thành công nếu tên task vượt quá 255 ký tự và tên được trả về bị cắt còn 255 ký tự; kiểm tra PR được liên kết gh-157790 để xem công việc đang được thực hiện.