[codex] Refactor Ghost fingerprint into package

[nahiyankhan]

🤖 Raised by Codex on behalf of Nahiyan.

Summary

• Refactors Ghost fingerprint handling into a package-oriented model shared across core, drift, fingerprint, and fleet flows.
• Adds map scope support and fingerprint package validation pieces in @ghost/core.
• Updates the docs, skill bundle references, CLI manifest, and tests for the package/surface-scoped fingerprint shape.

Notes

This is the base PR for the related stacked branches:

• codex/ghost-fingerprint-package-refactor
• codex/ghost-drift-repair-hints-v2

Validation

• Not run in this pass; this PR packages existing local branch work.