Silent no-op code reported network policies as applied when none were enforced

A software developer discovered that a deployment pipeline had been writing network policy rules to a database table for years, but no code ever read those rows to enforce actual firewall rules on any machine. The pipeline's 'apply network policies' step returned success without doing anything, giving operators a false sense that ingress and egress traffic was being filtered. To fix this, the developer added two explicit methods — enforces() and unavailableReason() — to a firewall interface contract, making capability an explicit, actionable return value rather than a silent assumption. The unenforced driver now throws on apply(), and the deployment step records 'Skipped' with a reason instead of reporting success. As an additional safeguard, unrecognized port exposure values default to binding on loopback, ensuring a configuration typo can never accidentally open a port.