Install GitHub CLI in release-publish job

[Finesssee]

Summary

• add a new Install GitHub CLI step before the upload step in the release-publish job
• downloads the latest gh Windows amd64 zip from GitHub releases, extracts it, and adds it to PATH
• skips installation if gh is already available

Root cause

The publish script uses gh (GitHub CLI) for all GitHub API operations. The CircleCI Windows runner does not have gh pre-installed.

Validation

• circleci config validate passed
• release-pipeline.tests.ps1 passed
• no version files changed

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