Replace Delighted for NPS surveys

### Is your feature request related to a problem?

Delighted is shutting down on June 30, 2026: https://delighted.com/sunset

### Describe the solution you'd like.

We will need to decide on and ship a replacement for Delighted before that date.

### Describe alternatives you've considered

* Remove NPS surveys altogether
* Use HubSpot Service Hub to deliver NPS surveys in-app or via email, which we don't currently pay for

### Additional context

_No response_