Add comprehensive thesis management system with database migration

This commit introduces a complete thesis management interface and migrates
the system from YAML-based storage to SQLite:

Core Changes:
- Add Database.php helper class with PDO connection and entity management
- Add list.php for viewing all theses with filtering and sorting
- Add edit.php for modifying existing thesis records
- Add import.php for migrating legacy YAML data to SQLite
- Add justfile with development tasks (serve, init-test-db, etc.)

Documentation:
- Add MIGRATION.md with complete migration guide and architecture docs
- Update README.md with database setup and Just recipe instructions
- Update .gitignore to exclude test databases and error logs

Modified Forms:
- Enhanced formulaire.php with transaction-based SQLite processing
- Updated index.php with database-driven form options
- Improved thanks.php to read from database views

The new architecture provides:
- Normalized database schema (19 tables, 2 views)
- Transaction safety and referential integrity
- CRUD operations for thesis management
- Filtering by year, orientation, AP program, publication status
- Secure file handling with metadata tracking

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

front-backend/index.php

@@ -3,61 +3,73 @@ ini_set('display_errors', 0);
 ini_set('log_errors', 1);
 ini_set('error_log', 'error.log');
 
-require_once 'vendor/autoload.php';
-
-use Symfony\Component\Yaml\Yaml;
+require_once 'Database.php';
 
 $page = isset($_GET['page']) ? intval($_GET['page']) : 1;
 $itemsPerPage = 10;
 
-$dir = "data/yaml/*.yaml";
-$yamlFiles = glob($dir);
-$data = [];
-
-foreach ($yamlFiles as $yamlFile) {
-  $data[] = Yaml::parseFile($yamlFile);
+try {
+    $db = Database::getInstance();
+    $offset = ($page - 1) * $itemsPerPage;
+    $itemsToLoad = $db->getPublishedTheses($itemsPerPage, $offset);
+    $totalItems = $db->countPublishedTheses();
+    $totalPages = ceil($totalItems / $itemsPerPage);
+} catch (Exception $e) {
+    error_log("Error loading theses: " . $e->getMessage());
+    $itemsToLoad = [];
+    $totalPages = 0;
 }
 
-usort($data, function ($a, $b) {
-  return $a['année'] <=> $b['année'];
-});
-
-$offset = ($page - 1) * $itemsPerPage;
-$itemsToLoad = array_slice($data, $offset, $itemsPerPage);
-
 include 'inc/header.php'; ?>
 
 <section class="section">
   <div class="container">
     <div class="columns is-multiline">
 
-      <?php foreach ($itemsToLoad as $key => $item): ?>
+      <?php foreach ($itemsToLoad as $item): ?>
         <div class="column is-one-fifth">
-          <a href="memoire.php?file=<?= urlencode($yamlFiles[$key]); ?>" class="card-link">
+          <a href="memoire.php?id=<?= $item['id']; ?>" class="card-link">
             <div class="card">
-              <?php if (isset($item['couverture'])): ?>
+              <?php
+              // Get cover image from thesis_files if available
+              $coverImage = null;
+              if (!empty($item['id'])) {
+                $files = $db->getThesisFiles($item['id']);
+                foreach ($files as $file) {
+                  $ext = strtolower(pathinfo($file['file_path'], PATHINFO_EXTENSION));
+                  if (in_array($ext, ['jpg', 'jpeg', 'png', 'gif']) && $file['file_type'] === 'main') {
+                    $coverImage = $file['file_path'];
+                    break;
+                  }
+                }
+              }
+              ?>
+              <?php if ($coverImage): ?>
                 <div class="card-image">
                   <figure class="image ">
-                    <img src="<?= $item['couverture']; ?>" alt="Image preview">
+                    <img src="<?= htmlspecialchars($coverImage); ?>" alt="Image preview">
                   </figure>
                 </div>
               <?php endif; ?>
               <div class="card-content">
                 <h4 class="title is-4">
-                  <?= $item['titre']; ?>
+                  <?= htmlspecialchars($item['title']); ?>
                 </h4>
                 <h2 class="subtitle">
-                  <?= $item['auteurice']; ?>
-                </p>
+                  <?= htmlspecialchars($item['authors'] ?? 'Auteur inconnu'); ?>
+                </h2>
                 <h3 class="tag title is-6 is-link is-light">
-                  <?= $item['année']; ?>
-              </h3>
+                  <?= htmlspecialchars($item['year']); ?>
+                </h3>
                 <p class="block content">
                   <?php
                   $excerpt_length = 150;
-                  $description_excerpt = substr($item['description'], 0, $excerpt_length) . '...';
+                  $synopsis = $item['synopsis'] ?? '';
+                  $description_excerpt = strlen($synopsis) > $excerpt_length
+                    ? substr($synopsis, 0, $excerpt_length) . '...'
+                    : $synopsis;
                   ?>
-                  <?= $description_excerpt; ?>
+                  <?= htmlspecialchars($description_excerpt); ?>
                 </p>
               </div>