feat: licence page, admin pages editor, license types, gradient card placeholders, latest-year home view

- Feature 1: public /licence.php fetches 'licenses' page from DB, renders Markdown
- Feature 1: nav.php adds 'Licence' link with active state
- Feature 2: Database::getPage(), savePage(), getAllPages() methods
- Feature 2: bundled src/Parsedown.php (MIT, zero-dependency)
- Feature 2: apropos.php now renders 'about' page content from DB via Parsedown
- Feature 2: admin/pages.php (list) + admin/pages-edit.php (EasyMDE editor)
- Feature 2: admin/actions/page.php (auth+CSRF+validation+save)
- Feature 2: admin/head.php adds 'Pages statiques' nav link
- Feature 3: storage/schema.sql seeds 8 CC license types
- Feature 3: storage/migrations/003_seed_license_types.sql (applied to live DB)
- Feature 3: Database::getLicenseTypes() / getAllLicenseTypes()
- Feature 3: admin/add.php + formulaire.php: license_id field on add form
- Feature 3: admin/edit.php: license_id field on edit form with raw FK lookup
- Feature 3: tfe.php: shows 'Licence :' meta row when non-null
- Feature 6: main.css: .card__media--gradient styles
- Feature 6: index.php: deterministic HSL gradient placeholder cards
- Feature 6: Database::getLatestYearTheses() + getLatestPublishedYear()
- Feature 6: index.php default home = random latest-year theses with info label

public/index.php

@@ -3,9 +3,12 @@
 require_once __DIR__ . '/../config/bootstrap.php';
 require_once APP_ROOT . '/src/Database.php';
 
-$page = isset($_GET["page"]) ? intval($_GET["page"]) : 1;
+$page = isset($_GET["page"]) ? max(1, intval($_GET["page"])) : 1;
 $year = isset($_GET["year"]) ? intval($_GET["year"]) : null;
-$itemsPerPage = 24; // bigger grid
+$itemsPerPage = 24;
+
+// Default home view: random theses from latest year (no year filter, no explicit page)
+$isDefaultView = (!$year && $page === 1);
 
 try {
     $db = Database::getInstance();
@@ -14,19 +17,25 @@ try {
 
     if ($year) {
         $itemsToLoad = $db->searchTheses(['year' => $year], $itemsPerPage, $offset);
-        $totalItems = $db->countSearchResults(['year' => $year]);
+        $totalItems  = $db->countSearchResults(['year' => $year]);
+    } elseif ($isDefaultView) {
+        $latestYear  = $db->getLatestPublishedYear();
+        $itemsToLoad = $db->getLatestYearTheses($itemsPerPage);
+        $totalItems  = count($itemsToLoad); // no pagination on default view
     } else {
         $itemsToLoad = $db->getPublishedTheses($itemsPerPage, $offset);
-        $totalItems = $db->countPublishedTheses();
+        $totalItems  = $db->countPublishedTheses();
     }
 
-    $totalPages = ceil($totalItems / $itemsPerPage);
+    $totalPages = $isDefaultView ? 1 : (int)ceil($totalItems / $itemsPerPage);
 } catch (Exception $e) {
     error_log("Error loading theses: " . $e->getMessage());
     $itemsToLoad = [];
-    $totalPages = 0;
+    $totalPages  = 0;
     $availableYears = [];
-    $totalItems = 0;
+    $totalItems  = 0;
+    $latestYear  = null;
+    $isDefaultView = false;
 }
 
 $currentNav = '';
@@ -61,6 +70,10 @@ $currentNav = '';
         Année : <?= htmlspecialchars($year) ?>
         <a href="index.php" class="clear-filter">✕ Réinitialiser</a>
     </div>
+    <?php elseif ($isDefaultView && !empty($latestYear)): ?>
+    <div class="filter-info home-latest-label">
+        Découvrez les TFE de <?= (int)$latestYear ?> — sélection aléatoire
+    </div>
     <?php endif; ?>
 
     <main class="home-main">
@@ -70,28 +83,31 @@ $currentNav = '';
                     <div class="card">
                         <div class="card__media">
                             <?php
-                            // Use first image/video file as thumbnail
+                            // Resolve thumbnail: banner_path → cover file → gradient placeholder
                             $thumb = null;
-                            if (!empty($item['files'])) {
-                                foreach ($item['files'] as $f) {
-                                    $ext = strtolower(pathinfo($f['file_path'], PATHINFO_EXTENSION));
-                                    if (in_array($ext, ['jpg','jpeg','png','gif','webp'])) {
-                                        $thumb = $f['file_path'];
-                                        break;
-                                    }
-                                }
-                            }
-                            // Also check cover image
-                            if (!$thumb && !empty($item['cover_image'])) {
-                                $thumb = $item['cover_image'];
+
+                            // 1. Banner path (dedicated home thumbnail)
+                            if (!empty($item['banner_path'])) {
+                                $thumb = $item['banner_path'];
                             }
+
+                            // 2. Cover image from thesis_files (not returned by view — skip for now)
+                            // 3. Fall through to gradient
                             ?>
                             <?php if ($thumb): ?>
                                 <img src="/media.php?path=<?= urlencode($thumb) ?>"
                                      alt="<?= htmlspecialchars($item['title']) ?>"
                                      loading="lazy">
                             <?php else: ?>
-                                <div class="card__media--placeholder">◻</div>
+                                <?php
+                                $hue  = ($item['id'] * 47 + 160) % 360;
+                                $hue2 = ($hue + 40) % 360;
+                                ?>
+                                <div class="card__media--gradient"
+                                     style="background:linear-gradient(135deg,hsl(<?= $hue ?>,60%,65%),hsl(<?= $hue2 ?>,55%,45%));">
+                                    <span class="card__gradient-author"><?= htmlspecialchars($item['authors'] ?? '') ?></span>
+                                    <span class="card__gradient-title"><?= htmlspecialchars($item['title']) ?></span>
+                                </div>
                             <?php endif; ?>
                         </div>
                         <div class="card__info">