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_modules/resolve/test/resolver/nested_symlinks/mylib/sync.js

@@ -0,0 +1,12 @@
+var a = require.resolve('buffer/').replace(process.cwd(), '$CWD');
+var b = require('resolve').sync('buffer/', { preserveSymlinks: true }).replace(process.cwd(), '$CWD');
+var c = require('resolve').sync('buffer/', { preserveSymlinks: false }).replace(process.cwd(), '$CWD');
+
+console.log(a, ': require.resolve, preserveSymlinks ' + (process.execArgv.indexOf('preserve-symlinks') > -1 ? 'true' : 'false'));
+console.log(b, ': preserveSymlinks true');
+console.log(c, ': preserveSymlinks false');
+
+if (a !== b && a !== c) {
+    throw 'sync: no match';
+}
+console.log('sync: success! a matched either b or c\n');