feat: Add presence heartbeat for Matrix online status

- matrix-gateway: POST /internal/matrix/presence/online endpoint
- usePresenceHeartbeat hook with activity tracking
- Auto away after 5 min inactivity
- Offline on page close/visibility change
- Integrated in MatrixChatRoom component

node-network-app/node_modules/any-promise/optional.js

@@ -0,0 +1,6 @@
+"use strict";
+try {
+  module.exports = require('./register')().Promise || null
+} catch(e) {
+  module.exports = null
+}