fix: remove unwired "Play video" button from homepage (en/mk/si)

The homepage "Every Student Has a Story" section had a <button class=
"play-button"> with no handler and no video wired to it — clicking did
nothing. Remove the dead button; keep the team photo and section copy.
The story video can be wired back in later.

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

en/index.html

@@ -246,7 +246,6 @@
             <div class="video-container">
                 <img width="1920" height="1280" loading="lazy" decoding="async" src="../images/about_us-timeline-milestones_img0.webp" alt="MSOS team group photo" class="video-thumbnail">
                 <div class="video-overlay"></div>
-                <button class="play-button" aria-label="Play video"></button>
             </div>
             <div class="team-content">
                 <h2>Every Student Has a Story, Here’s Ours</h2>