Impact Hub Preview Governance Overview

This sample document is included so public document library routes can be
reviewed immediately in Vercel. Production uploads are stored in the private
Supabase governance-docs bucket and served through signed URLs.

Document controls:
- Public documents can appear in the public library.
- Member documents require an authenticated organization member.
- Admin documents require an organization admin role.
- Version history is tracked through the replaces_document_id relationship.