[macOS] Rebuild dyld shared cache for latest stable Xcode

[erik-bershel]

Description

• https://developer.apple.com/documentation/xcode-release-notes/xcode-26_1-release-notes#Known-Issues

Simulators may fail to boot during the first build after upgrading macOS. (152328794)

Workaround: Execute xcrun simctl runtime dyld_shared_cache update --all prior to booting the simulator to ensure dyld shared cache generation has completed.

The practice of forcing cache creation should generally have a positive impact on performance.

Related issue:

Check list

• Related issue / work item is attached
• Tests are written (if applicable)
• Documentation is updated (if applicable)
• Changes are tested and related VM images are successfully generated

[Copilot]

Pull Request Overview

This PR implements a workaround for a known Xcode 26.1 issue where simulators may fail to boot after macOS upgrades by rebuilding the dyld shared cache for the latest stable Xcode version.

• Adds a new Update-DyldCache function to identify and update the dyld shared cache for the latest stable Xcode
• Integrates the cache update process into the Xcode installation workflow (excluding macOS Sonoma)

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
images/macos/scripts/helpers/Xcode.Installer.psm1	Adds Update-DyldCache function to rebuild dyld shared cache for latest stable Xcode
images/macos/scripts/build/Install-Xcode.ps1	Integrates dyld cache update into installation process with Sonoma exclusion

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