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/@nodelib/fs.walk/out/readers/sync.d.ts

@@ -0,0 +1,15 @@
+import * as fsScandir from '@nodelib/fs.scandir';
+import type { Entry } from '../types';
+import Reader from './reader';
+export default class SyncReader extends Reader {
+    protected readonly _scandir: typeof fsScandir.scandirSync;
+    private readonly _storage;
+    private readonly _queue;
+    read(): Entry[];
+    private _pushToQueue;
+    private _handleQueue;
+    private _handleDirectory;
+    private _handleError;
+    private _handleEntry;
+    private _pushToStorage;
+}