chore: bump Ghost to 6.47.0; 6.46.0:0 → 6.47.0:0

[helix-nine]

Upstream bump

Bumps Ghost from 6.46.0 → 6.47.0 (ghost:6.47.0-alpine on Docker Hub). MySQL pin unchanged.

Highlights (6.47.0)

• ✨ Added a beta of the automations feature.
• 🐛 Fixed themes with custom error templates returning HTTP 500.
• 🐛 Fixed paid members on other tiers receiving gated newsletter content.
• 🐛 Fixed the Portal offer link spinning forever for active paid members.
• 🐛 Improved upload error messages in the editor.

Full release notes: https://github.com/TryGhost/Ghost/releases/tag/v6.47.0

Package changes

• startos/manifest/index.ts: Ghost docker tag → 6.47.0-alpine.
• startos/versions/current.ts: version → 6.47.0:0, release notes updated in all locales. No migration required.

start-sdk already at latest (1.5.3); npm update was a no-op.

Test plan

• npm run check (tsc) — green.

[helix-nine]

Thanks for the review and merge, @MattDHill. Ghost 6.47.0 is out the door.