Fix ppaged crash on SIGKILL of pager

Ensure terminal settings and foreground process group are restored after
the pager process exits. This prevents 'termios.error' crashes in
prompt_toolkit when the pager is killed abnormally (e.g. SIGKILL),
which can leave the terminal in an inconsistent state.

Author: tleonhardt

cmd2/cmd2.py

@@ -1611,6 +1611,29 @@ def ppaged(
                 )
                 pipe_proc.communicate(output_bytes)
 
+                # If the pager was killed (e.g. SIGKILL), the terminal might be in a bad state.
+                # Attempt to restore terminal settings and foreground process group.
+                if self.stdin.isatty():
+                    try:
+                        import signal
+                        import termios
+
+                        # Ensure we are in the foreground process group
+                        if hasattr(os, 'tcsetpgrp') and hasattr(os, 'getpgrp'):
+                            # Ignore SIGTTOU to avoid getting stopped when calling tcsetpgrp from background
+                            old_handler = signal.signal(signal.SIGTTOU, signal.SIG_IGN)
+                            try:
+                                os.tcsetpgrp(self.stdin.fileno(), os.getpgrp())
+                            finally:
+                                signal.signal(signal.SIGTTOU, old_handler)
+
+                        # Restore terminal attributes
+                        if self._initial_termios_settings is not None:
+                            termios.tcsetattr(self.stdin.fileno(), termios.TCSANOW, self._initial_termios_settings)
+
+                    except (ImportError, OSError, termios.error):
+                        pass
+
         else:
             self.poutput(
                 *objects,