Increase default stack guard on x86 Windows

[gregg-miskelly]

In Microsoft Cloud Test environments, the target process would crash without stopping when running under a managed debugger and the target process triggered a stack overflow exception. This increases the default count of thread guard pages to avoid this.

[Copilot]

Pull Request Overview

This PR increases the default stack guard pages on x86 Windows to prevent crashes in Microsoft Cloud Test environments when a managed debugger encounters stack overflow exceptions. The change restructures the conditional compilation logic to provide more consistent guard page allocation across platforms.

• Consolidates debug-specific guard page logic under a single INDEBUG macro
• Increases default guard pages for 32-bit platforms from 0 to 1 page
• Maintains existing 64-bit platform defaults (3 pages plus debug overhead)

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[tommcdon]

LGTM, thanks!

[janvorli]

LGTM, thank you!

[janvorli]

I have noticed that the comments at the changed code about various sizes are completely outdated, we should either remove it completely or update it to match the reality.
Edit: I don't mean doing it as part of this PR.

[janvorli]

I've created #118401 to track the comment update.

[gregg-miskelly]

@janvorli can you merge this for me? I don't have rights