Why: Legacy upload events and synced duty flows need the same private-data and current-state guarantees as new member work.
Evidence: Real legacy SSE leakage and independent duty replay findings; correction evidence remains in the canonical task record.
Impact: Describe trusted per-event sharing and durable duty versions without new mandatory downstream interfaces or runtime changes.
Refs: system-project-membership r1.1; Dev feature/project-member-access
Why: Joined members must see one globally named project and keep private conversations and source documents.\n\nEvidence: Proposal links the fixed implementation plan, explicit authorization and task evidence without claiming deployment or CI success.\n\nImpact: Define optional lifecycle extension, identity recovery, private reads and published knowledge for U2/U3/U5.\n\nRefs: Dev feature/project-member-access