[RTB] Rotate expired GHCR token for ghost-stack workflows

[noahwhite]

Task Summary

Rotate the expired GHCR (GitHub Container Registry) token that is causing the "Log in to GHCR" step to fail in ghost-stack CI/CD workflows.

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✅ Acceptance Criteria

• Generate new GHCR token with appropriate permissions (write:packages)
• Update GitHub repository secret with new token
• Verify workflows run successfully with new token
• Document expiration date of new token (if applicable)

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📝 Additional Context

• Symptom: "Log in to GHCR" step failing in one or more workflows
• Affected workflows: TBD (check which workflows use GHCR login)
• Token location: GitHub repository secrets

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📦 Definition of Ready

• Acceptance criteria defined
• No unresolved external dependencies
• Story is estimated
• Team has necessary skills and access
• Priority is clear
• Business value understood

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✅ Definition of Done

• All acceptance criteria met
• Workflows passing with new token
• Token expiration tracked (if applicable)

[linear]

GHO-43