Enable IntelliSense prediction by default

[daxian-dbw]

PR Summary

Enable intellisense prediction by default:

• when VT is not supported, PredictionSource is set to None by default
• when VT is supported and it's running with PowerShell 7.2+, PredictionSource is set to HistoryAndPlugin by default
• when VT is supported and it's running with PowerShell prior to 7.2, PredictionSource is set to History by default

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: Enable the predictive intellisense by default in PSReadLine MicrosoftDocs/PowerShell-Docs#8943

Microsoft Reviewers: Open in CodeFlow

[daxian-dbw]

@andschwa Can you please review this PR when you get a chance? Thanks!

[daxian-dbw]

@andschwa Thanks for the review!

[ghost]

🎉 v2.2.6 has been released which incorporates this pull request. 🎉