Add external URL health checks in CI/CD

This commit adds automated checks for dead external URLs in the
documentation during CI/CD pipeline. It configures
`remark-lint-no-dead-urls` plugin with custom ignore patterns to handle
false positives.
This commit adds URL aliveness checks in CI/CD that was previously
missing, adding ignore rules for false negatives.

Changes:

- Add missing external URL checking in GitHub workflow.
- Add ignore patterns for false negatives.
- Remove fail fast feature from quality checks to receive results from
  all commands.

.github/workflows/quality-checks.yaml

@@ -11,7 +11,9 @@ jobs:
           - lint:css
           - lint:md
           - lint:md:urls:relative
+          - lint:md:urls:external
           - lint:md:consistency
+      fail-fast: false # Still interested to see results from other commands
     steps:
       - name: Checkout
         uses: actions/checkout@v4

.remark-lint-no-dead-urls.mjs

@@ -0,0 +1,19 @@
+import remarkLintNoDeadUrls from 'remark-lint-no-dead-urls';
+
+/** @type {import('remark-lint-no-dead-urls').Options} */
+const Options = {
+  skipUrlPatterns: [
+    // These return 403 (Forbidden) to checks
+    'codepen.io', // 'https://codepen.io'
+  ].map(buildUrlPattern),
+};
+
+/** @type {Omit<import('unified-engine').Preset} */
+export default {
+  plugins: [[remarkLintNoDeadUrls, Options]],
+};
+
+function buildUrlPattern(fqdn) {
+  const escaped = fqdn.replace(/\./g, '\\.');
+  return `^https://${escaped}/.*$`;
+}

README.md

@@ -199,7 +199,7 @@ You can choose one of the following existing themes to begin:
 
 ##### Custom Themes
 
-Or you can create your own theme & import it. Check example themes at [existing themes](./src/themes/). [The HTML](./src/ez-consent.js#L18) uses only a few classes using [BEM](http://getbem.com/naming/) naming convention.
+Or you can create your own theme & import it. Check example themes at [existing themes](./src/themes/). [The HTML](./src/ez-consent.js#L18) uses only a few classes using [BEM](https://getbem.com/naming/) naming convention.
 
 You can also add your own class names using `css_classes` option, see [initialization](#2-initialize) for details.
 

package.json

@@ -11,7 +11,7 @@
     "lint:css": "stylelint \"**/*.css\"",
     "lint:md": "markdownlint **/*.md --ignore node_modules",
     "lint:md:urls:relative": "remark . --frail --use remark-validate-links",
-    "lint:md:urls:external": "remark . --frail --use remark-lint-no-dead-urls",
+    "lint:md:urls:external": "remark . --frail --rc-path .remark-lint-no-dead-urls.mjs",
     "lint:md:consistency": "remark . --frail --use remark-preset-lint-consistent"
   },
   "repository": {