Close all editors in split on :q execution

Is your feature request related to a problem? Please describe.

Coming from native Vim, I've always used :q to close a split when it's not needed anymore. Since using VSCode-Vim I've found it a bit frustrating having only the current tab close when using :q.

Describe the solution you'd like

It'd be good to have a boolean user setting that, when toggled to true, will close all tabs in a split when :q is executed.

Believe it or not, I've actually already implemented this with automated tests in my own fork. I'm making this issue retrospectively. It'd be cool to make a PR for this.

Describe alternatives you've considered

For about a year during my old job, I've used the following setting to achieve this behavior. It's pretty hacky though because command rebinding isn't a thing in VSCode-Vim.

{
  "vim.commandLineModeKeyBindingsNonRecursive": [
    { "before": [ "q", "<cr>" ], "commands": [ "workbench.action.closeEditorsInGroup" ] }
  ],
}

Start by tracing the :q command handling and the VS Code editor-group close behavior; the issue does not name specific files or entry points. Compare the requested boolean setting with the existing command-line keybinding workaround, then use or recreate the automated tests mentioned by the reporter to verify that :q closes all editors in the current split when enabled.