Resizing the window should keep the prompt at the bottom of the window

### Windows Terminal version

1.19.105.73.0

### Windows build number

10.0.19045.4239

### Other Software

_No response_

### Steps to reproduce

- open a Windows Terminal
- fill the buffer so that the prompt appears at the bottom of the window
- resize the window so that it's smaller than before
- enlarge the window

### Expected Behavior

The prompt should stay at the bottom of the window.

### Actual Behavior

The prompt has moved several lines up (scroll position appears to be correct: at the bottom of the window, but the text/prompt's position is not correct). Also notice one of the previous prompt that incorrectly appears on the top right, but I guess it should go in another issue.

https://github.com/microsoft/terminal/assets/199648/680ee2d6-eefe-46e1-87b8-3616571cfe1a

The expected behavior is the one I saw on popular terminal apps on macOS and Linux.

For example:

iTerm on mac

https://github.com/microsoft/terminal/assets/199648/6dcf7daa-b07d-43b7-b77d-9905a3ca6b3d

GNOME Terminal on Debian

https://github.com/microsoft/terminal/assets/199648/06862b6e-70fb-4337-a8da-aad169115199

Start by reproducing the resize sequence described in the issue on Windows Terminal 1.19.105.73.0, then trace the window-resize handling and prompt positioning behavior. Done means shrinking and enlarging a window keeps the prompt at the bottom, matching the expected behavior described and demonstrated in the issue.

Written by the indexing model from the issue text.