feat(workshops): VHS Worms 2026 workshops with improved styling

- Add 4 VHS Worms 2026 courses (Feb-Jun 2026)
- Use markdown-native Material grid cards design
- Fix page rendering (remove workshops blog plugin)
- Add equal height cards via flexbox CSS
- Remove awkward checkmark pseudo-elements
- Make page full-width layout (hide navigation sidebar)

Courses: KI-Chatbots (Feb 21), KI-Einsatz im Beruf (Mar 14),
Videos mit KI (Apr 18), Programmieren mit KI (Jun 20)

mkdocs.yml

@@ -67,15 +67,6 @@ plugins:
       pagination: true
       archive: true
       authors: true
-  - blog:
-      blog_dir: workshops
-      blog_toc: false
-      post_url_format: "{slug}"
-      post_date_format: "dd.MM.yyyy"
-      archive: false
-      pagination: false
-      categories: true
-      categories_toc: true
   - search
   - redirects:
       redirect_maps: