Fix anonymous audit (e.g. Feature Flags, filter Insights by Creator)

Feature request

Is your feature request related to a problem?

Various features in PostHog show a list of users that performed actions on an object. However in quite a few cases, the email is not shown, only the avatar and the name. But if the name is blank you just have an anonymous audit trail. Not very useful.

Examples:

• Feature flags (easily the most annoying/dangerous one)
• Survey changelog
• Cohort changelog

The Members list is also very unhelpful:

Describe the solution you'd like

I can understand why some customers may not wish to enforce names; and perhaps this messes with automatic account provisioning. But I'd like one or more of the following to resolve this:

• Togglable setting (or hardcoded behavior) to force users to set names on invite accept
• Allow Owner/Admin accounts to set user names
• Toggleable setting (or hardcoded behavior) to have users use the names the Inviter set during the Invite flow. (I don't know why in the vast majority of cases these names are being wiped).
• Show user names in changelogs (can be Admin-only)
• Reveal user names in changelogs on avatar hover (can be Admin-only action)

Describe alternatives you've considered

Asking 120+ users to manually set their name in a product they infrequently use? Not a realistic alternative.

Additional context

• Weakens security posture if the Feature Flag audit trail has no human-readable actors.
• Makes my job as admin more difficult. I want to be able to see at a glance that certain members who have requested access are onboarded. Emails are less easy to read than names (e.g. first initial -dot- surname pattern).

Debug info

The issue names Feature Flags, Survey changelog, Cohort changelog, and the Members list but no files or tests. First narrow the request to one actor-name behavior and trace that surface; done should mean the selected audit or member view consistently shows an identifiable human-readable actor without requiring each user to set a name manually.