feat(news): add Meet Student Slovenia 2026 event page

Trilingual (EN/MK/SI) promo page for the upcoming "Meet Student Slovenia
2026" event, built through the content CMS (content/news/...) plus custom
sections styled to match the site.

- Guide-style centred header with a wide banner hero and caption
- Plain-background key facts (When/Where), subtle live-stream line,
  centred Register CTA, and partner/patron/sponsor logos
  (NLB Banka, Embassy of Slovenia; Capital Financial Center as text)
- Auto-scrolling "Moments from previous years" carousel + inline photos
- Embedded registration form (dropdowns, required study-plan fields,
  multi-field study preferences) wired to a Google Form; left-hand
  floating Register button
- Homepage promo banner (EN/MK/SI) + auto-listed in News hub, homepage
  latest, sitemap, llms.txt and the offline search index
- New assets: css/pages/_event.css, event-register.js

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

llms.txt

@@ -64,6 +64,7 @@ AI summary: https://msosorg.com/links-for-bots/about-msos/
 
 ## News
 - [News and updates](https://msosorg.com/en/news/): Everything new at MSOS in one place — events and projects, blog stories, announcements and official updates for Macedonian students in Slovenia.
+- [Meet Student Slovenia 2026](https://msosorg.com/en/news/meet-student-slovenia-2026/)
 - [Proof-of-means amount updated to €507,43 per month](https://msosorg.com/en/news/proof-of-means-updated-2026/): If you are applying for or renewing a student residence permit in Slovenia, you must prove you have enough money to support yourself. That requirement is tied…
 
 ## Events & projects