Retry outbound read syncs for up to 24 hours

ts/util/waitForOnline.ts

@@ -3,19 +3,33 @@
 
 export function waitForOnline(
   navigator: Readonly<{ onLine: boolean }>,
-  onlineEventTarget: EventTarget
+  onlineEventTarget: EventTarget,
+  options: Readonly<{ timeout?: number }> = {}
 ): Promise<void> {
-  return new Promise(resolve => {
+  const { timeout } = options;
+
+  return new Promise((resolve, reject) => {
     if (navigator.onLine) {
       resolve();
       return;
     }
 
     const listener = () => {
-      onlineEventTarget.removeEventListener('online', listener);
+      cleanup();
       resolve();
     };
 
+    const cleanup = () => {
+      onlineEventTarget.removeEventListener('online', listener);
+    };
+
     onlineEventTarget.addEventListener('online', listener);
+
+    if (timeout !== undefined) {
+      setTimeout(() => {
+        cleanup();
+        reject(new Error('waitForOnline: did not come online in time'));
+      }, timeout);
+    }
   });
 }