[User Story] Update Ghost 6 Docker Compose stack to latest release

[noahwhite]

Story Summary

As a platform maintainer, I want to update the Ghost 6 Docker Compose stack to the latest stable release, so that the CMS benefits from upstream bug fixes, security patches, and improvements.

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✅ Acceptance Criteria

Define "done" in clear, testable terms (Given/When/Then if applicable).

• Given the updated images are pulled, when the Ghost stack is started, then containers start successfully.
• Given a database migration is required, when Ghost boots, then migrations complete without errors.
• Admin UI and public site are accessible after upgrade.
• Existing content and configuration remain intact.

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📝 Additional Context

• Design:
• Docs:
• Related Issues/PRs:

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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
• Unit/integration tests written & passing
• Peer-reviewed
• Docs updated (if applicable)
• Verified in staging (if needed)
• No critical bugs/regressions

[linear]

GHO-20