docs(fogstack): refresh pack readiness for Office, Lattice, and Registry surfaces

[mdheller]

Summary

Clean non-draft replacement for closed draft PR #326. Refreshes FogStack pack readiness after recent upstream Office collaboration, Lattice Studio/Data/GovernAI, and registry-root/lifecycle/signature-hardening work.

Changes

• Updates catalog/fogstack-packs-v0.1.yaml:
  • adds fogstack.office at 55% executable-demo posture
  • adds fogstack.registry at 60% after filesystem registry, root metadata, rollback/revocation lifecycle index, local registry metadata signature verification, and schema hardening
  • upgrades fogstack.data to Data / GovernAI at 50% fixture-ready product-surface posture
  • upgrades fogstack.ai to AI / Lattice Studio at 45% fixture-ready product-surface posture
  • preserves repository_strategy: single-repo-for-now
• Updates docs/FOGSTACK_PACKS.md with matching pack prose.
• Updates docs/FOGSTACK_STATUS.md with:
  • Office, Data/GovernAI, and AI/Lattice offering slices
  • registry-root / rollback-revocation / local signature-verification / strict-schema maturity
  • corrected readiness matrix
  • remaining gaps for network registry, production signing/identity, client enforcement, CLI exit-code hygiene, and operator UX

Safety boundary

• Docs/catalog only.
• No runtime code changes.
• No new repos.
• No pack ID renames.
• No claim of external registry, production deployment, KMS/HSM signing, live data backend, live inference/training, or client-side rollback enforcement.

Closes #321.
Review gate: #328.
Supersedes closed draft PR #326.

[mdheller]

Parking this docs/status-readiness refresh for now.

We are shifting priority to executable development work, starting with PR #332 (fogstack: add one-command local release demo). This PR can be revisited later if/when the status/readiness docs need cleanup, but it should not block current implementation work.