Fix parsing hotkeys for non english chars

[bn45hkurr0y4]

This fixes an issue related to incorrect key handling in non-English keyboard layouts (in my case, the Russian CTRL + C shortcut).
I've had this problem for a long time and no one has fixed it yet, but with the help of AI, I discovered that the issue stems from incorrect handling of the Cyrillic alphabet.
Please test this patch, because I don’t know if it might affect something else and cause errors.

This fixes #1393 and #2865

PR Summary

PR Checklist

• PR has a meaningful title
• 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

Microsoft Reviewers: Open in CodeFlow

[Copilot]

Pull request overview

This PR addresses a long-standing issue where Ctrl+letter hotkeys (notably Ctrl+C) can be mis-parsed under non-English Windows keyboard layouts (e.g., Russian), causing PSReadLine key binding matching to fail.

Changes:

• Skips the Windows ToUnicodeEx-based translation for standard Ctrl+letter control characters (\x01–\x1A) to keep chord normalization layout-independent.
• Adds inline comments explaining why Ctrl+letter chords should bypass layout-dependent translation to preserve key binding matching.

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[Copilot]

This change alters how Ctrl+letter chords are normalized on Windows, but there’s no automated coverage to prevent regressions (especially for non-English layouts like ru-RU). Please add a unit/integration test that validates Ctrl+C (and ideally a couple other Ctrl+letter chords) still normalize to the expected Latin chord string even when the active keyboard layout is Russian (skip the test if the layout isn’t available on the runner).