Add Y bounds check to InvokePrompt (Fixes #4790)

[jftkcs]

PR Summary

Aligns behavior with that stated in issue #4790:

• Add a bounds check to make calls to InvokePrompt silently return if it's not possible to redraw the entire prompt and no Y position was specified by the caller.
• Check and directly throw an exception if a call is made to InvokePrompt with an explicit Y position that is not possible.

Since implicit callers (i.e. those not specifying a Y position) can't know where the prompt will get written, they can't guard against accidentally trying to update a prompt that's left the buffer. The only thing that can be done by anyone once the prompt has left the screen is to accept the line or abort.

Explicit callers passing a Y value in 'arg' at least know where they are trying to write the prompt so we can throw the exception and let them handle/recover (if desired).

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: Update PSReadline documentation for InvokePrompt behavior change. MicrosoftDocs/PowerShell-Docs#12157

Microsoft Reviewers: Open in CodeFlow