search.php: semantic HTML overhaul of répertoire index and results view

- Replace 4x <div class="repertoire-col"> with <section>; remove
  .repertoire-col__header class, CSS now targets section > h2
- Wrap all index link groups in <ul>/<li>; delete the four per-column
  link classes (year-index-item, cat-index-item, student-index-item,
  keyword-index-item); active state switches from .active to
  aria-current="page" on the <a>
- Add <h1 class="sr-only">Répertoire</h1> so the index view has a
  page-level heading (WCAG 2.4.6)
- Remove redundant <div class="search-results-view"> wrapper; padding
  moved to .results-grid and .search-results-header directly
- Replace <div class="results-grid"> with <ul class="results-grid">;
  each result card becomes <li><a class="result-card">
- Replace <span class="result-card__meta"> with <small> (ancillary
  metadata per HTML spec)
- Replace result-count <p> with <output role="status"> (computed value)
- Replace 3x <div class="search-filter-group"><label>…</label><select>
  with <label> directly wrapping <select> (implicit association,
  removes .search-filter-group divs); CSS updated to display:flex on
  the label itself
- Pagination wrapper changed to <nav aria-label="Pagination">;
  page-info span gets aria-current="page"
- search.css: delete .search-results-view, four index-item classes,
  .cat-index-group, .search-filter-group; consolidate years/other
  column link styles under .repertoire-col:first-child ul a and
  .repertoire-col:not(:first-child) ul a selectors; add ul reset rule

public/assets/search.css

@@ -52,7 +52,7 @@
   border-right: none;
 }
 
-.repertoire-col__header {
+.repertoire-col > h2 {
   font-size: 0.72rem;
   letter-spacing: 0.1em;
   text-transform: uppercase;
@@ -63,8 +63,15 @@
   border-bottom: 1px solid var(--border-color);
 }
 
+/* Strip list chrome inside repertoire columns */
+.repertoire-col ul {
+  list-style: none;
+  margin: 0;
+  padding: 0;
+}
+
 /* Years column - big bold numbers */
-.year-index-item {
+.repertoire-col:first-child ul a {
   display: block;
   font-size: 2.2rem;
   font-weight: 700;
@@ -76,16 +83,12 @@
   letter-spacing: -0.02em;
 }
 
-.year-index-item:hover,
-.year-index-item.active {
+.repertoire-col:first-child ul a:hover,
+.repertoire-col:first-child ul a[aria-current] {
   color: var(--purple);
 }
 
 /* Categories column */
-.cat-index-group {
-  margin-bottom: 0.6rem;
-}
-
 .cat-index-label {
   font-size: 0.72rem;
   letter-spacing: 0.08em;
@@ -97,7 +100,8 @@
   margin-top: 0.75rem;
 }
 
-.cat-index-item {
+/* Categories, students, keywords columns — shared link style */
+.repertoire-col:not(:first-child) ul a {
   display: block;
   font-size: 0.95rem;
   color: var(--black);
@@ -107,57 +111,26 @@
   transition: color 0.15s;
 }
 
-.cat-index-item:hover,
-.cat-index-item.active {
-  color: var(--purple);
-}
-
-/* Students column */
-.student-index-item {
-  display: block;
-  font-size: 0.95rem;
-  color: var(--black);
-  text-decoration: none;
-  padding: 0.1rem 0;
-  line-height: 1.4;
-  transition: color 0.15s;
-}
-
-.student-index-item:hover {
-  color: var(--purple);
-}
-
-/* Keywords column */
-.keyword-index-item {
-  display: block;
-  font-size: 0.95rem;
-  color: var(--black);
-  text-decoration: none;
-  padding: 0.1rem 0;
-  line-height: 1.4;
-  transition: color 0.15s;
-}
-
-.keyword-index-item:hover,
-.keyword-index-item.active {
+.repertoire-col:not(:first-child) ul a:hover,
+.repertoire-col:not(:first-child) ul a[aria-current] {
   color: var(--purple);
 }
 
 /* ---- Search results view (grid) ---- */
-.search-results-view {
-  padding: 1rem 1.5rem;
-}
-
 .search-results-header {
+  display: block;
   font-size: 0.85rem;
   color: var(--text-muted);
-  margin-bottom: 1rem;
+  margin: 1rem 1.5rem 0.5rem;
 }
 
 .results-grid {
   display: grid;
   grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
   gap: 1.5rem;
+  list-style: none;
+  margin: 0;
+  padding: 0.5rem 1.5rem 1.5rem;
 }
 
 .result-card {
@@ -187,6 +160,7 @@
 .result-card__meta {
   font-size: 0.78rem;
   color: var(--purple);
+  font-style: normal;
 }
 
 /* Toggle button (index/results) */
@@ -229,18 +203,17 @@
   flex-wrap: wrap;
 }
 
-.search-filter-group {
+/* label now wraps the select directly — flex aligns label text + select */
+.search-filter-label {
   display: flex;
   align-items: center;
   gap: 0.4rem;
-}
-
-.search-filter-label {
   font-size: 0.78rem;
   color: var(--text-muted);
   text-transform: uppercase;
   letter-spacing: 0.06em;
   white-space: nowrap;
+  cursor: default;
 }
 
 .search-filter-select {