Display name on tags

Feature request

Is your feature request related to a problem?

Some event's have a more technical naming, or two types of users might call the event different things.

Describe the solution you'd like

We used to have Mixpanel, and there they have a "Lexicon" feature, where I can add description, upload media same as Posthog, but I can also add "Display name" and "tags". Display name basically allows you to "rename" a event within Posthog, allowing for easier to consume names for humans.
So event signed_up_confirmed (part of multiple sign up steps) could be "Signed up" and that is a verified event reducing the risk that someone uses signup_form_sent for example.

Describe alternatives you've considered

We looking into hiding and verifiying some events + description to guide users but still suboptimal coming from using this a lot in Mixpanel.

Additional context

https://docs.mixpanel.com/docs/data-governance/lexicon

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 reviewing the Mixpanel Lexicon reference linked in the issue and PostHog’s existing event description, hiding, and verification flows. The issue names no files, tests, or entry points, so first define how display names and tags should appear and be managed before implementation. Done should include the requested event metadata behavior and coverage for it.