Removes docs/solutions/windows/scripts/install-yellowkey-extension.ps1
(thin wrapper that fetched Allen's upstream installer) and updates the
policy's run_script.path to install-windows-yellowkey-extension.ps1, the
canonical filename in allenhouchins/fleet-extensions. Users drop Allen's
installer (with its canonical name) into their GitOps scripts directory;
the policy references it directly.
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remove if NA -->
**Related issue:** #46360
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## Summary by CodeRabbit
* **Documentation**
* Updated Windows YellowKey osquery Fleet policy documentation with
revised script references and remediation instructions for hosts that
fail to load the extension.
* **Chores**
* Removed obsolete installation script; installation procedures have
been consolidated for improved clarity and maintainability.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Co-authored-by: Claude <noreply@anthropic.com>
