Subscription pause UX: pause reason, accurate paused-state messaging, label customization

Improve the subscription-pause experience end to end. Asks: when a client pauses their service, prompt them with a 'pause reason' dropdown (budget, workload, waiting for feedback, custom) so the agency learns why; fix the misleading 'max concurrent requests reached' message that currently shows for paused accounts and instead clearly indicate the account is paused with a clear unpause CTA; and customizable details/labels on pause states.