PostgreSQL provider introduces scheduled backups

The CloudNative PostgreSQL provider now supports scheduled backups, letting you define recurring backup schedules directly in your instance storage configuration.

Add schedules to any entry in spec.backup.storages[] to create CNPG ScheduledBackup resources automatically. Each schedule can target a specific storage backend and run on a custom cron expression.

Scheduled backups are available now. Backup schedules are managed by the provider and will appear in the cluster automatically.