Clearer payment recovery

When a paid subscription renewal cannot be collected, SlideDrift now shows a payment alert across the workspace, Create page, and carousel library. The account menu also identifies the subscription as overdue while preserving the name of the affected plan.

The alert links directly to Stripe's payment page when one is available. If the payment needs bank authentication, the message explains that step; otherwise you can use the billing portal to resolve the renewal and restore paid access.