PR Summary

Fixes completion of variables assigned inside Do loops while the variable to complete is also inside the Do loop. For example:

    do
    {
        $Test = ls
        $Tes<Tab>
    }
    until ($x -gt 0)

This would not complete as it would visit the until condition before the statement block, and because it's after the cursor it would stop visiting the remaining asts.

PR Context

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• Breaking changes
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  • Experimental feature(s) needed
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• User-facing changes
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  • Documentation needed
    - [ ] Issue filed:
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  • N/A or can only be tested interactively
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• Tooling
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    • Impact on PowerShell Editor Services which is used in the PowerShell extension for VSCode
      (which runs in a different PS Host).
      • Issue filed:
    • Impact on Completions (both in the console and in editors) - one of PowerShell's most powerful features.
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