Description of the new feature/enhancement

This issue suggests implementing a "Vi mode" similar to the very convenient one implemented by Alacritty, where the user can
move the cursor around, select and copy text using the keyboard alone in a fashion familiar to most programmers and power users;

• The user presses a predefined keyboard shortcut to enter Vi mode
• Once in Vi mode, the cursor is movable in the current terminal buffer using Vi motions (h j k l)
• 'V' enters visual mode, where text can be selected and copied ('y')
• '/' and '?' enter search mode where text can be searched and then copied