focused but hidden cmdline window

## Describe the bug

When pressing down arrow below the last line of code, if the cmdline window was hidden, it's focused but it's still hidden, which is very confusing. We don't know what is happening and keys don't seem to work, one has to guess that ctrl-x must be pressed.

## To Reproduce
Steps to reproduce the behavior:
1. set `hide_cmdline_win = True` in `pudb.cfg`
2. run pudb and show a file long enough
3. scroll down to the end of file
4. press down arrow (this will focus the cmdline window)

## Expected behavior

Either:
- show the cmdline window if it was hidden
- or don't focus the cmdline window, because it wasn't shown, so it shouldn't get the focus

## Versions

What version of pudb? `2024.1.2`