Improve URL checks to reduce false-negatives

This commit improves the URL health checking mechanism to reduce false
negatives.

- Treat all 2XX status codes as successful, addressing issues with codes
  like `204`.
- Exclude URLs within Markdown inline code blocks.
- Send the Host header for improved handling of webpages behind proxies.
- Improve formatting and context for output messages.
- Fix the defaulting options for redirects and cookie handling.
- Add URL exclusion support for non-responsive URLs.
- Update the user agent pool to modern browsers and platforms.
- Improve CI/CD workflow to respond to modifications in the
  `test/checks/external-urls` directory, offering immediate feedback on
  potential impacts to the external URL test.
- Add support for randomizing TLS fingerprint to mimic various clients
  better, improving the effectiveness of checks. However, this is not
  fully supported by Node.js's HTTP client; see nodejs/undici#1983 for
  more details.
- Use `AbortSignal` instead of `AbortController` as more modern and
  simpler way to handle timeouts.

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

@@ -1,64 +1,62 @@
 import { sleep } from '@/infrastructure/Threading/AsyncSleep';
-import { getUrlStatus, type IRequestOptions } from './Requestor';
-import { groupUrlsByDomain } from './UrlPerDomainGrouper';
-import type { IUrlStatus } from './IUrlStatus';
+import { getUrlStatus, type RequestOptions } from './Requestor';
+import { groupUrlsByDomain } from './UrlDomainProcessing';
+import type { FollowOptions } from './FetchFollow';
+import type { UrlStatus } from './UrlStatus';
 
 export async function getUrlStatusesInParallel(
   urls: string[],
-  options?: IBatchRequestOptions,
-): Promise<IUrlStatus[]> {
-  // urls = [ 'https://privacy.sexy' ]; // Here to comment out when testing
+  options?: BatchRequestOptions,
+): Promise<UrlStatus[]> {
+  // urls = ['https://privacy.sexy']; // Comment out this line to use a hardcoded URL for testing.
   const uniqueUrls = Array.from(new Set(urls));
-  const defaultedOptions = { ...DefaultOptions, ...options };
-  console.log('Options: ', defaultedOptions);
-  const results = await request(uniqueUrls, defaultedOptions);
+  const defaultedDomainOptions = { ...DefaultDomainOptions, ...options?.domainOptions };
+  console.log('Batch request options applied:', defaultedDomainOptions);
+  const results = await request(uniqueUrls, defaultedDomainOptions, options);
   return results;
 }
 
-export interface IBatchRequestOptions {
-  domainOptions?: IDomainOptions;
-  requestOptions?: IRequestOptions;
+export interface BatchRequestOptions {
+  readonly domainOptions?: Partial<DomainOptions>;
+  readonly requestOptions?: Partial<RequestOptions>;
+  readonly followOptions?: Partial<FollowOptions>;
 }
 
-interface IDomainOptions {
-  sameDomainParallelize?: boolean;
-  sameDomainDelayInMs?: number;
+interface DomainOptions {
+  readonly sameDomainParallelize?: boolean;
+  readonly sameDomainDelayInMs?: number;
 }
 
-const DefaultOptions: Required<IBatchRequestOptions> = {
-  domainOptions: {
-    sameDomainParallelize: false,
-    sameDomainDelayInMs: 3 /* sec */ * 1000,
-  },
-  requestOptions: {
-    retryExponentialBaseInMs: 5 /* sec */ * 1000,
-    requestTimeoutInMs: 60 /* sec */ * 1000,
-    additionalHeaders: {},
-  },
+const DefaultDomainOptions: Required<DomainOptions> = {
+  sameDomainParallelize: false,
+  sameDomainDelayInMs: 3 /* sec */ * 1000,
 };
 
 function request(
   urls: string[],
-  options: Required<IBatchRequestOptions>,
-): Promise<IUrlStatus[]> {
-  if (!options.domainOptions.sameDomainParallelize) {
+  domainOptions: Required<DomainOptions>,
+  options?: BatchRequestOptions,
+): Promise<UrlStatus[]> {
+  if (!domainOptions.sameDomainParallelize) {
     return runOnEachDomainWithDelay(
       urls,
-      (url) => getUrlStatus(url, options.requestOptions),
-      options.domainOptions.sameDomainDelayInMs,
+      (url) => getUrlStatus(url, options?.requestOptions, options?.followOptions),
+      domainOptions.sameDomainDelayInMs,
     );
   }
-  return Promise.all(urls.map((url) => getUrlStatus(url, options.requestOptions)));
+  return Promise.all(
+    urls.map((url) => getUrlStatus(url, options?.requestOptions, options?.followOptions)),
+  );
 }
 
 async function runOnEachDomainWithDelay(
   urls: string[],
-  action: (url: string) => Promise<IUrlStatus>,
+  action: (url: string) => Promise<UrlStatus>,
   delayInMs: number | undefined,
-): Promise<IUrlStatus[]> {
+): Promise<UrlStatus[]> {
   const grouped = groupUrlsByDomain(urls);
   const tasks = grouped.map(async (group) => {
-    const results = new Array<IUrlStatus>();
+    const results = new Array<UrlStatus>();
     /* eslint-disable no-await-in-loop */
     for (const url of group) {
       const status = await action(url);