Add support for a keymap to maximize pane horizontally

[sviatoslav-hr]

Currently zed has a keymap to maximize pane:

"ctrl-w _": "vim::MaximizePane",

But it only works vertically, meaning it only affects height of the pane. I think, most people split panes vertically, making this keymap not that useful.

It would be really nice to have a keymap to maximize pane horizontally. In vim the keymap is ctrl-w |, so in the keymap settings it can look something like this:

"ctrl-w |": "vim::MaximizePaneHorizontally",

Note: I'm assuming this is just a missing feature, not a bug

If this gets an approval, but it's not a priority for zed team, I can try to contribute this myself.

[ankitpal1029]

This would honestly be amazing! I really miss the maximize mode on vscode where on move to a pane it maximizes by default, currently i use toggle zoom but it's not quite the same