fix: persistent sessiebeheer (remember-me), HTTPS-cookie herstel en Microsoft OAuth signed state flow

auth/logout.php

@@ -6,6 +6,21 @@
 require_once __DIR__ . '/../includes/auth.php';
 start_secure_session();
 
+// Vernietig persistente login in database
+if (!empty($_SESSION['user_id'])) {
+    try {
+        $db = get_db_connection();
+        ensure_remember_token_columns($db);
+        $stmt = $db->prepare("UPDATE users SET remember_token = NULL, remember_token_expires_at = NULL WHERE id = ?");
+        $stmt->execute([$_SESSION['user_id']]);
+    } catch (Throwable $e) {
+        // Stil negeren bij uitloggen
+    }
+}
+
+// Verwijder remember cookie
+clear_remember_cookie();
+
 // Vernietig alle sessie variabelen
 $_SESSION = [];