Complete task 4 backend security architecture docs

Taskmaster/Tasks/task-4-4.md

@@ -1,23 +1,23 @@
 ---
 taskmaster_id: "4.4"
-status: "pending"
+status: "done"
 priority: "high"
 depends_on: ["2"]
 parent_id: "4"
 source: "taskmaster"
-generated_at: "2026-05-24T07:15:25.199Z"
+generated_at: "2026-05-24T07:26:29.052Z"
 ---
 
 # 4.4 - Create authorization matrix for REST and Socket.IO
 
-- [ ] 4.4 - Create authorization matrix for REST and Socket.IO #taskmaster #priority/high #status/pending ⏫ 🆔 tm-4-4 ⛔ tm-2
+- [x] 4.4 - Create authorization matrix for REST and Socket.IO #taskmaster #priority/high #status/done ⏫ 🆔 tm-4-4 ⛔ tm-2
 
 ## Metadata
 
 | Field | Value |
 | --- | --- |
 | Taskmaster ID | 4.4 |
-| Status | pending |
+| Status | done |
 | Priority | high |
 | Dependencies | 2 |
 | Parent | 4 - Define backend security and refactor strategy from latest audit |
@@ -28,6 +28,8 @@ Map every endpoint and realtime event to access level, ownership checks, state p
 
 ## Details
 
+Completed. Produced `09 - Audits/Authorization Matrix - REST and Socket.IO.md` and `09 - Audits/Realtime Authorization Spec.md`.
+
 Include public/authenticated/owner/buyer/seller/admin/support/service-role classifications. Socket.IO rooms must be server-derived from authenticated identity, not client-supplied user IDs.
 
 ## Verification