Put huge banners on the dashboard warning people that if there is a time gap between free tier and paid tier THEY WILL LOSE EVENTS IN THAT GAP FOR EVER!

Feature request

Is your feature request related to a problem?

Yes. I lost all events for 36 hours because I didn't have any billing alerts and didn't set up paid billing fast enough.

Describe the solution you'd like

This is not for me but "For Those That Come After" (good for you if you get the reference ;) )

Prominent banners on the UI warning users who have reached 80-90% of their free plan that they will lose their events if they don't update billing before they reach the end of the free plan. This should be easy.

Describe alternatives you've considered

I don't think you should really do the banners... I go on posthog daily and I would have seen them. You probably sent us a bunch of emails but we missed those.

Additional context

None. I love Posthog, keep it up!

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]

Start by tracing the dashboard UI for free-plan usage and the existing billing-alert flow. Confirm how usage thresholds are exposed, then define the banner behavior for users approaching the free-plan limit; done means the warning is prominent and explains that events in the gap before paid billing are lost.