Don't immediately close the external console window when the program ends

Type: Debugger

Describe the bug

• OS and Version: Windows 10
• VS Code Version: 1.47.3
• C/C++ Extension Version: 0.29.0
• Other extensions you installed (and if the issue persists after disabling them): none

When debugging and running C/C++ code on an external console ("externalConsole": true in launch.json), the console window is immediately closed at the end of the program.

This is inconvenient, as there can be some output we are interested in and that we are unable to read as the console window is immediately closed.

There are workarounds to that, like putting a breakpoint in the last return 0; line of main(), or adding cin.ignore(); cin.get(); lines, or getch(), or system("PAUSE");, or something similar.
But these are not optimal solutions.

The best experience would be to just have the external console to prompt the user to press a key before it gets closed (like the debugger would automatically invoke a system("PAUSE") before closing the external console).

This behavior could be made customizable with something like "externalConsolePauseAtExit": true/false in launch.json.

Start by locating the launch.json handling for externalConsole and the Windows debugger process-exit path. Run a minimal C/C++ program with externalConsole enabled and verify that the external window can pause before closing, with the behavior controlled by the proposed configuration option.