Update release pipeline to use msrustup 1.95

[SteveL-MSFT]

PR Summary

Create parameter defaulting to known good version
Add parameter to Windows pipeline
Update pipeline to use this parameter

[Copilot]

Pull request overview

This PR updates the build/release tooling to use a newer “known good” Microsoft Rust toolchain (msrustup ms-prod-1.95), and threads that version through the Azure Pipelines templates so the Rust toolchain version is centrally controlled.

Changes:

• Bump the msrustup channel used by the build helpers to ms-prod-1.95.
• Introduce a Rust toolchain version variable in the official pipeline and pass it into the Windows build template.
• Replace hard-coded rustVersion values in pipeline tasks with the new parameter/variable-driven value.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
helpers.build.psm1	Updates msrustup channel selection to ms-prod-1.95.
.pipelines/DSC-Windows.yml	Adds a Rust version template parameter used by the Rust installer task.
.pipelines/DSC-Official.yml	Defines a central Rust version and uses it across Windows and Linux build steps.