gh-135329: prevent infinite traceback loop on Ctrl-C under external programs

When running Python REPL under another program (e.g., strace) and pressing Ctrl-C,
termios raises `EIO` during terminal state restoration, causing infinite exception tracebacks.

This patch catches `termios.error` with `errno.EIO` in `reader.prepare()` to avoid
recursive failure loops when restoring console state.

Author: dura0ok

Lib/_pyrepl/reader.py

@@ -30,6 +30,8 @@
 from . import commands, console, input
 from .utils import wlen, unbracket, disp_str, gen_colors, THEME
 from .trace import trace
+import termios
+import errno
 
 
 # types
@@ -590,6 +592,10 @@ def prepare(self) -> None:
             self.dirty = True
             self.last_command = None
             self.calc_screen()
+        except termios.error as e:
+            if e.args[0] == errno.EIO:
+                return
+            raise
         except BaseException:
             self.restore()
             raise