pyrepl loses input and mis-positions cursor when F2 is pressed

Bug report

Bug description:

This is bad for 2 different reasons:

1. pyrepl loses track of the cursor, thinking it's in the first column when it's actually in the middle of the screen somewhere, so future screen drawing operations have unexpected results
2. on top of that, anything you were in the middle of typing when you pressed F2 is discarded, so if you wanted to access the history to copy something out and paste it into the command you're writing, oops, it's gone

CPython versions tested on:

3.13

Operating systems tested on:

Linux

Linux 上で CPython 3.13 を使って pyrepl の F2 の動作を再現し、その後 F2 の処理と画面再描画のパスを追跡します。現在の入力が保持され、カーソルが正しく配置されたままになり、その後の画面描画が正常に動作すれば完了です。