add composer-unused, comprehensive docs, and project restructure

- Add icanhazstring/composer-unused as dev dependency for dependency hygiene checks
- Add German documentation (docs/) covering architecture, conventions, workflows, and developer checklists
- Add API layer (ApiAuth, ApiBootstrap, ApiResponse), audit, scheduler, custom fields, and SSO services
- Add Microsoft OIDC SSO, API token management, and user lifecycle features
- Add swagger-ui vendor integration and OpenAPI spec
- Add production Docker setup and bin/ scripts
- Update composer dependencies, config, templates, and frontend assets throughout

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/Service/Auth/RememberMeService.php

@@ -79,13 +79,16 @@ class RememberMeService
         if (!empty($user['locale'])) {
             I18n::$locale = (string) $user['locale'];
         }
-        $userId = (int) ($user['id'] ?? 0);
+        $userId = (int) $user['id'];
         if ($userId > 0) {
             PermissionService::getUserPermissions($userId, true);
             AuthService::loadTenantDataIntoSession($userId);
-            if (empty($_SESSION['no_active_tenant'])) {
-                UserRepository::updateLastLogin($userId);
+            if (!empty($_SESSION['no_active_tenant'])) {
+                // Enforce the same tenant policy as interactive login.
+                AuthService::logout();
+                return false;
             }
+            UserRepository::updateLastLogin($userId, 'local');
         }
 
         $newToken = bin2hex(random_bytes(32));