feat: jury composition + banner image upload

- migration 004: thesis_supervisors.role + is_external; view adds jury_president/jury_promoteurs/jury_lecteurs
- migration 005: theses.banner_path; view exposes t.banner_path and t.license_id
- Database: getThesisJury(), setThesisJury(), setBannerPath()
- admin/add.php: jury fieldset (président/promoteur/lecteurs + externe checkboxes, JS add/remove rows); banner file input
- admin/edit.php: jury fieldset pre-populated from DB; banner preview + remove checkbox + upload; multipart form
- admin/actions/formulaire.php: parse jury fields → setThesisJury(); banner upload to banners/
- tfe.php: three conditional jury rows (président·e, promoteur·ice, lecteur·ices)
- schema.sql: updated thesis_supervisors, theses, v_theses_full, v_theses_public definitions
- admin.css: fieldset, jury-row, jury-entry, btn-remove styles

src/Database.php

@@ -731,6 +731,60 @@ class Database {
         return $this->getLicenseTypes();
     }
 
+    // ========================================================================
+    // JURY METHODS
+    // ========================================================================
+
+    /**
+     * Fetch all jury members for a thesis, with role and is_external flag.
+     */
+    public function getThesisJury(int $thesisId): array {
+        $stmt = $this->pdo->prepare("
+            SELECT s.id, s.name, ts.role, ts.is_external, ts.supervisor_order
+            FROM thesis_supervisors ts
+            JOIN supervisors s ON s.id = ts.supervisor_id
+            WHERE ts.thesis_id = ?
+            ORDER BY ts.supervisor_order
+        ");
+        $stmt->execute([$thesisId]);
+        return $stmt->fetchAll();
+    }
+
+    /**
+     * Replace the entire jury for a thesis in a single transaction.
+     * $juryMembers: array of ['name' => string, 'role' => string, 'is_external' => int]
+     */
+    public function setThesisJury(int $thesisId, array $juryMembers): void {
+        $this->pdo->prepare("DELETE FROM thesis_supervisors WHERE thesis_id = ?")->execute([$thesisId]);
+        $stmt = $this->pdo->prepare("
+            INSERT INTO thesis_supervisors (thesis_id, supervisor_id, role, is_external, supervisor_order)
+            VALUES (?, ?, ?, ?, ?)
+        ");
+        foreach ($juryMembers as $order => $member) {
+            $name = trim($member['name'] ?? '');
+            if ($name === '') continue;
+            $supervisorId = $this->findOrCreateSupervisor($name);
+            $role       = in_array($member['role'], ['president', 'promoteur', 'lecteur'])
+                            ? $member['role'] : 'promoteur';
+            $isExternal = isset($member['is_external']) ? (int)$member['is_external'] : 0;
+            $stmt->execute([$thesisId, $supervisorId, $role, $isExternal, $order + 1]);
+        }
+    }
+
+    // ========================================================================
+    // BANNER METHODS
+    // ========================================================================
+
+    /**
+     * Set (or clear) the banner_path for a thesis.
+     */
+    public function setBannerPath(int $thesisId, ?string $path): void {
+        $stmt = $this->pdo->prepare(
+            "UPDATE theses SET banner_path = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?"
+        );
+        $stmt->execute([$path, $thesisId]);
+    }
+
     /**
      * Insert a thesis file record
      */