`NameError` has different actions when be raised in IDLE

Bug report

Bug description:

In IDLE, I raised three different exceptions. The output is:

>>>raise Exception("123\n456")
Traceback (most recent call last):
  File "<pyshell#0>", line 1, in <module>
    raise Exception("123\n456")
Exception: 123
456
>>>raise NameError("123\n456")
Traceback (most recent call last):
  File "<pyshell#1>", line 1, in <module>
    raise NameError("123\n456")
456
>>>raise OSError("123\n456")
Traceback (most recent call last):
  File "<pyshell#2>", line 1, in <module>
    raise OSError("123\n456")
OSError: 123
456

Only NameError cannot show the Exception Type if the text has two or more lines.
In shell the action is same with other exception.

CPython versions tested on:

3.13

Operating systems tested on:

Windows

Linked PRs

• gh-135526

先在 Python 3.13 的 IDLE shell 中重現這三個例外情況，並將其與一般 shell 的輸出進行比較。追蹤 IDLE 如何格式化多行例外訊息，接著確認多行 NameError 顯示的例外類型是否與 Exception 和 OSError 一致；連結的 PR gh-135526 顯示相關工作已經在進行中。