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+---
+id: TASK-20
+title: Add membership endpoints and bidirectional shape sync
+status: Done
+assignee: []
+created_date: '2026-02-17 22:35'
+labels: []
+dependencies: []
+priority: high
+---
+
+## Description
+
+<!-- SECTION:DESCRIPTION:BEGIN -->
+space_members table + CRUD API in EncryptID server for centralized membership. Automerge CommunityDoc extended with members map. PATCH endpoint for module→canvas bidirectional shape updates.
+<!-- SECTION:DESCRIPTION:END -->