Refactor and improve external URL checks

- Move external URL checks to its own module under `tests/`. This
  separates them from integration test, addressing long runs and
  frequent failures that led to ignoring test results.
- Move `check-desktop-runtime-errors` to `tests/checks` to keep all
  test-related checks into one directory.
- Replace `ts-node` with `vite` for running
  `check-desktop-runtime-errors` to maintain a consistent execution
  environment across checks.
- Implement a timeout for each fetch call.
- Be nice to external sources, wait 5 seconds before sending another
  request to an URL under same domain. This solves rate-limiting issues.
- Instead of running test on every push/pull request, run them only
  weekly.
- Do not run tests on each commit/PR but only scheduled (weekly) to
  minimize noise.
- Fix URLs are not captured correctly inside backticks or parenthesis.

tests/checks/external-urls/StatusChecker/ExponentialBackOffRetryHandler.ts

@@ -0,0 +1,48 @@
+import { sleep } from '@/infrastructure/Threading/AsyncSleep';
+import { IUrlStatus } from './IUrlStatus';
+
+const DefaultBaseRetryIntervalInMs = 5 /* sec */ * 1000;
+
+export async function retryWithExponentialBackOff(
+  action: () => Promise<IUrlStatus>,
+  baseRetryIntervalInMs: number = DefaultBaseRetryIntervalInMs,
+  currentRetry = 1,
+): Promise<IUrlStatus> {
+  const maxTries = 3;
+  const status = await action();
+  if (shouldRetry(status)) {
+    if (currentRetry <= maxTries) {
+      const exponentialBackOffInMs = getRetryTimeoutInMs(currentRetry, baseRetryIntervalInMs);
+      // tslint:disable-next-line: no-console
+      console.log(`Retrying (${currentRetry}) in ${exponentialBackOffInMs / 1000} seconds`, status);
+      await sleep(exponentialBackOffInMs);
+      return retryWithExponentialBackOff(action, baseRetryIntervalInMs, currentRetry + 1);
+    }
+  }
+  return status;
+}
+
+function shouldRetry(status: IUrlStatus) {
+  if (status.error) {
+    return true;
+  }
+  return isTransientError(status.code)
+    || status.code === 429; // Too Many Requests
+}
+
+function isTransientError(statusCode: number) {
+  return statusCode >= 500 && statusCode <= 599;
+}
+
+function getRetryTimeoutInMs(
+  currentRetry: number,
+  baseRetryIntervalInMs: number = DefaultBaseRetryIntervalInMs,
+) {
+  const retryRandomFactor = 0.5; // Retry intervals are between 50% and 150%
+  // of the exponentially increasing base amount
+  const minRandom = 1 - retryRandomFactor;
+  const maxRandom = 1 + retryRandomFactor;
+  const randomization = (Math.random() * (maxRandom - minRandom)) + maxRandom;
+  const exponential = 2 ** (currentRetry - 1);
+  return Math.ceil(exponential * baseRetryIntervalInMs * randomization);
+}