feat(applications): add configurable stop grace period

Add centralized stop grace period resolution for application settings and use it across manual stops, preview stops, and deployments. Validate the Livewire advanced setting against shared min/max constants and cover persistence, fillable creation, and fallback behavior with tests.

bootstrap/helpers/constants.php

@@ -36,6 +36,8 @@ const VALID_CRON_STRINGS = [
 ];
 const RESTART_MODE = 'unless-stopped';
 const DEFAULT_STOP_GRACE_PERIOD_SECONDS = 30;
+const MIN_STOP_GRACE_PERIOD_SECONDS = 1;
+const MAX_STOP_GRACE_PERIOD_SECONDS = 3600;
 
 const DATABASE_DOCKER_IMAGES = [
     'bitnami/mariadb',