[codex] Align Summon Ghost demo sandboxes

[nahiyankhan]

Summary

• Add a server-side Ghost scan compatibility adapter that normalizes canonical .ghost/fingerprint/manifest.yml packages, legacy .ghost/fingerprint.yml roots, and newer scanner API names when available.
• Align Surface Gallery and Generate around mirrored SurfacePolicy presets, including Ghost-root presets and shared Ghost payload metadata.
• Make Generate send surfacePolicy by default, keeping raw surfacePlan behind the advanced custom config panel.
• Update docs for canonical Ghost package layout, legacy compatibility, and the Gallery vs Generate demo roles.
• Fix sandbox repaint behavior when token CSS changes respawn a sandbox with existing section HTML.

Validation

• pnpm --filter @summon-internal/demo-server test
• pnpm --filter @summon-internal/demo test
• pnpm --filter @summon-example/surface-gallery test
• pnpm --filter @summon-example/surface-gallery test:e2e
• pnpm test:safety
• pnpm build

Notes

I attempted to bump @anarchitecture/ghost to ^0.7.1, but the configured npm registry reports 0.2.0 as latest and no matching ^0.7.1 version. The local adapter dynamically uses the newer scanner function names when the approved package or mirror is available, while preserving installability with the current dependency.