Project pages: add ToC sidebar to all remaining articles (EN/MK/SI)

Give the 23 project pages that used a single-column layout the same scrollspy
table-of-contents sidebar as the others (built from their <h2> sections, with
language-agnostic section-N ids so it works for Cyrillic too), plus the mobile
ToC header. The "Like what we do?" sidebar CTA now sits under the ToC on every
non-memorial project page; the two memorial stories get the ToC but no CTA.
The full-width bottom CTA remains the mobile fallback.

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

en/projects/in-memory-of-frosina-kulakova/index.html

@@ -193,7 +193,28 @@
 <!-- END_HEADER -->
 
     <main class="article-page">
-        <article class="article-container">
+        <!-- Sticky Mobile Header -->
+        <div class="mobile-article-header">
+            <span id="mobile-article-title">In Memory of Frosina Kulakova</span>
+            <i class="fas fa-chevron-down"></i>
+            <div class="progress-bar-container">
+                <div class="progress-bar"></div>
+            </div>
+            <div class="mobile-scrollspy-dropdown">
+                <ul id="mobile-scrollspy-links"></ul>
+            </div>
+        </div>
+
+                <div class="article-layout-container">
+            <aside class="article-sidebar">
+                <nav class="scrollspy-nav">
+                    <ul>
+                        <li><a href="#section-1" class="active">A message of unity</a></li>
+                        <li><a href="#section-2">Closing thoughts</a></li>
+                    </ul>
+                </nav>
+            </aside>
+            <article class="article-container">
             <header class="article-header">
                 <p class="article-publish-date">Published on February 8, 2025</p>
                 <h1>In Memory of Frosina Kulakova</h1>
@@ -211,7 +232,7 @@
                     <img width="720" height="480" loading="lazy" decoding="async" src="../../../images/frosina-2.webp" alt="Students lighting candles in memory of Frosina">
                 </figure>
 
-                <h2>A message of unity</h2>
+                <h2 id="section-1">A message of unity</h2>
 
                 <p>This gathering was not about politics or criticism. It was about togetherness, humanity, and shared responsibility. As students abroad, we wanted to show that we care, that we remember, and that we hope for a better tomorrow where such injustices will no longer happen.</p>
 
@@ -221,7 +242,7 @@
                     <img width="720" height="480" loading="lazy" decoding="async" src="../../../images/frosina-3.webp" alt="Flowers and candles laid in remembrance">
                 </figure>
 
-                <h2>Closing thoughts</h2>
+                <h2 id="section-2">Closing thoughts</h2>
 
                 <p>Frosina’s story reminded us of the fragility of life and the importance of solidarity. We are grateful to all who came, who lit a candle, or who simply stood with us in silence.</p>
 
@@ -239,6 +260,7 @@
                     </div>
                 </section>
         </article>
+        </div>
         <section class="newsletter-cta">
             <div class="container">
                 <div class="cta-content">