Dispatch releases to ghost-internal

[chailandau]

Why

Published Ghost versions should update ghost-internal's pinned CLI without requiring GitHub Actions in the internal repository.

What

• Export the published Ghost version and use a scoped cross-organization GitHub App token
• Check out ghost-internal from the Ghost release workflow and update its package pin and lockfile
• Run ghost-internal's complete validation before creating or updating a version PR
• Leave migration failures visible and never auto-merge generated PRs
• Extend release-workflow checks to protect the synchronization wiring

Risk Assessment

Low — the synchronization is gated on a real publish and configured secrets, and skips cleanly elsewhere. It does not alter package publication or Homebrew synchronization.

Generated with Goose

[chailandau]

Closing because the proposed synchronization depends on unprovisioned cross-organization GitHub App credentials and cannot be exercised safely. No changes should merge.