Support command arguments for VisualEditing

[sharpchen]

PR Summary

Resolves #3214

Bash readline supports $EDITOR with command arguments, I wish to have this in PSReadLine as well.

export EDITOR='nvim --cmd "lua vim.env.foo = 1"'

$env:EDITOR = 'nvim --cmd "lua vim.env.foo = 1"'

This change adds following possible patterns for visual editor:

1. path/to/foo.exe --args
2. "path/with space/foo.exe" --args
3. foo.exe --args

Note that ProcessStartInfo.Arguments only allows " for quoting components, which is different from bash, this worth to be mentioned in documentation.
I didn't add test since I neither found an existing test for ViEditVisually nor am familiar enough with this repository to write from scratch.

PR Checklist

• PR has a meaningful title
  • Use the present tense and imperative mood when describing your changes
• Summarized changes
• Make sure you've added one or more new tests
• Make sure you've tested these changes in terminals that PowerShell is commonly used in (i.e. conhost.exe, Windows Terminal, Visual Studio Code Integrated Terminal, etc.)
• User-facing changes
  • Not Applicable
  • OR
  • Documentation needed at PowerShell-Docs
    • Doc Issue filed:

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