Repo: Port draft retirement life event thematic

Port of wet-boew/GCWeb#2691 (Thematic: Retirement life event):
* Extremely preliminary
* Barely a thematic at this point (more like sloppy custom CSS than a thematic atm)
* Checklist has custom JS that hasn't made its way into this PR yet
* Needs way more work

Changes to adapt it to this repo:
* Adapt to the repo's folder structure:
  * Migrate pages/metadata to the "pages" folder
  * Migrate supporting images to a new "assets" folder (currently orphaned):
    * GCWeb already uses "assets" for its images
    * Jekyll's documentation states that it uses "assets" as a common convention (according to https://jekyllrb.com/docs/step-by-step/07-assets/)
  * Migrate CSS/JS into the repo's life-events.css/js files (with "Retirement Hub theme" comment headers)
* ESLint config:
  * Add a global "wb" variable to resolve the following error in the "eslint:target" task:
    * 'wb' is not defined (no-undef)
  * More info: https://eslint.org/docs/latest/rules/no-undef
* Pages:
  * Repo index page:
    * Add link to thematic page
  * Theme page:
    * Frontmatter:
      * Change YAML to JSON
      * Adjust thematic CSS/JS file references
    * Revise note paragraph:
      * Change "méli-mélo/th-vitality/vitality.html" reference into a GitHub Pages link (relative path doesn't make sense outside of the GCWeb repo)
      * Remove note about wrong CSS file references (it's correctly referring to its own CSS now)
    * Use tab indents consistently (was previously a mix of 4 spaces and tabs)
  * Metadata:
    * Rename componentName variable's value to "th-retirement-hub" (to make metadata retrievable by the theme page's Liquid logic)
    * Rename leftover "empathy" references to "retirement"/"retirement-hub"

Author: EricDunsworth

.eslintrc.json

@@ -14,7 +14,8 @@
   },
   "globals": {
     "DOMPurify": "readonly",
-    "JSON": true
+    "JSON": true,
+    "wb": true
   },
   "rules": {
     "indent": ["error", "tab", { "outerIIFEBody": 0 }],

assets/th-retirement-hub/landing/banner-right.png

@@ -3,7 +3,7 @@
 	"title": "Événements de la vie sur Canada.ca",
 	"lang": "fr",
 	"altLangPage": "index.html",
-	"dateModified": "2026-02-27"
+	"dateModified": "2026-03-06"
 }
 ---
 
@@ -12,5 +12,6 @@
 <h2 id="test">Exemples pratiques</h2>
 
 <ul>
+	<li><a href="pages/th-retirement-hub/retirement-hub.html"><span lang="en">Retirement Hub theme</span> (anglais seulement)</a></li>
 	<li><a href="pages/page-fr.html">Gabarit de page</a></li>
 </ul>

assets/th-retirement-hub/landing/calculator.png

@@ -3,7 +3,7 @@
 	"title": "Canada Life Events",
 	"lang": "en",
 	"altLangPage": "index-fr.html",
-	"dateModified": "2026-02-27"
+	"dateModified": "2026-03-06"
 }
 ---
 
@@ -12,5 +12,6 @@
 <h2 id="test">Working examples</h2>
 
 <ul>
+	<li><a href="pages/th-retirement-hub/retirement-hub.html">Retirement Hub theme</a></li>
 	<li><a href="pages/page-en.html">Template page</a></li>
 </ul>