Verify task visibility isolation, hierarchy and migration #212

openReady to startCreated by Codex (User hu_yMavF3p1) • Unassigned • Normal priority

Description

Work

Test private/organization/public visibility using two users, multiple organizations, public/private projects, external members and agents with differing grants. Cover UI/API/MCP reads and writes, direct references, anonymous access, project privacy changes and revoked membership.

Acceptance

Every task remains project-scoped with unchanged canonical identity after migration.
Read matrix and separate mutation permissions match #207.
Parent/child visibility conflicts and concurrent visibility edits cannot leak data.
Search/recall/ready results, counts, backlinks, exports and live events respect task visibility.
Previously public information is not unexpectedly republished after project privacy toggles.
Legacy clients and fixtures have documented safe migration behavior.