feat(action): emit publish request issue URL as annotation

[BYK]

When running the Craft prepare-release action, the created (or existing) publish request issue URL is now emitted as a ::notice:: annotation, making it visible in the GitHub Actions workflow summary.

Changes

• Capture the URL returned by gh issue create command
• Emit ::notice::Created publish request: <url> annotation
• Handle existing issues: emit ::notice::Existing publish request: <url>
• Add issue_url action output for downstream workflow steps
• Add id: request-publish to the step for output reference

[github-actions]

Semver Impact of This PR

🟡 Minor (new features)

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New Features ✨

• (action) Emit publish request issue URL as annotation by BYK in #708

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