Update proof-of-means to 507,43 EUR, add announcement page, European number format (EN)

- Update the residence-permit "sufficient means" figure to 507,43 EUR/month
  (Slovenian basic minimum income from 1 April 2026, source gov.si) across the
  guide, FAQ, budget note, sample parent statement and my-route tip; replaces
  the old 484,88 everywhere.
- New standalone news announcement page /<lang>/news/proof-of-means-updated-2026/
  (trilingual), published 1 August 2026, with a clickable gov.si source box and a
  hero image (Pixabay, credited). news.js now supports announcement items
  (slug + body) and shows them newest-first on the homepage and News hub; the
  image doubles as the card thumbnail. Optimised 6.98MB to 255KB.
- Switch English EUR amounts to European format (comma decimal, dot thousands):
  507,43 / 9.600 / 1.000 etc. Only euro-prefixed amounts are touched, so SI/MK
  (which use a euro suffix) are unaffected. New generator eurofmt.js.

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

en/student-welcome-guide/student-residence-permit/index.html

@@ -232,7 +232,7 @@
 
                 <h3 class="guide-substage">Proof of sufficient means</h3>
 
-                <p>You must show you can support yourself. The most common route is a written statement from a parent or guardian, who is legally obliged to support you, declaring that they will support you (name, surname, date of birth) with at least €484.88 per month for the whole academic year. One parent signing is enough. Special notarisation is not required, but the statement must be written in English, Slovenian, or one of the former Yugoslav languages in Latin script. This €484.88 figure is tied to the Slovenian minimum-income basis and can change, so check the current amount. See the means and address page for other accepted proof such as student-work earnings, a scholarship, bank funds, or grants.</p>
+                <p>You must show you can support yourself. The most common route is a written statement from a parent or guardian, who is legally obliged to support you, declaring that they will support you (name, surname, date of birth) with at least €507,43 per month for the whole academic year. One parent signing is enough. Special notarisation is not required, but the statement must be written in English, Slovenian, or one of the former Yugoslav languages in Latin script. This €507,43 figure is tied to the Slovenian minimum-income basis and can change, so check the current amount. See the means and address page for other accepted proof such as student-work earnings, a scholarship, bank funds, or grants.</p>
 
                 <h3 class="guide-substage">Document with your handwritten signature</h3>