Rewrite WallClockListener as onTimeTravel

ts/util/startTimeTravelDetector.ts

@@ -0,0 +1,18 @@
+// Copyright 2017-2022 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+const INTERVAL = 1000;
+
+export function startTimeTravelDetector(callback: () => unknown): void {
+  let lastTime = Date.now();
+  setInterval(() => {
+    const currentTime = Date.now();
+
+    const sinceLastTime = currentTime - lastTime;
+    if (sinceLastTime > INTERVAL * 2) {
+      callback();
+    }
+
+    lastTime = currentTime;
+  }, INTERVAL);
+}