Improve surveys preview

[marandaneto]

Feature request

Is your feature request related to a problem?

Make the preview more interactive.
Show the preview on the user's page if possible with real positioning (maybe via the toolbar?).
The preview should behave as the real survey but it does not capture any response.

Describe the solution you'd like

Describe alternatives you've considered

Additional context

Debug info

- [ ] PostHog Cloud, Debug information: [please copy/paste from https://us.posthog.com/settings/project-details#variables]
- [ ] PostHog Hobby self-hosted with `docker compose`, version/commit: [please provide]
- [ ] PostHog self-hosted with Kubernetes (deprecated, see [`Sunsetting Kubernetes support`](https://posthog.com/blog/sunsetting-helm-support-posthog)), version/commit: [please provide]