FEAT: Integrated Matrix gateway and updated GTD

gtd.org

@@ -174,7 +174,16 @@ Slim down the org-agent microkernel by moving non-essential cognitive functions
     - Implemented `:signal` actuator for outbound responses.
     - Updated `org-skill-chat` to support Signal channel.
     - Verified with `gateway-signal-tests.lisp`.
-**** TODO Implement org-skill-gateway-matrix
+**** DONE Implement org-skill-gateway-matrix
+    CLOSED: [2026-04-11 Sat 17:15]
+    :PROPERTIES:
+    :ID: gateway-matrix-task
+    :END:
+    - Implemented `org-skill-gateway-matrix.org` (Client-Server API).
+    - Added background polling for `/sync` with token persistence.
+    - Implemented `:matrix` actuator for `m.room.message` delivery.
+    - Updated `org-skill-chat` to support Matrix channel and room IDs.
+    - Verified with `gateway-matrix-tests.lisp`.
 
 *** TRACK: DEPLOYMENT & INFRASTRUCTURE
 **** TODO Create Dockerfile and docker-compose.yml for containerized setup