Open-ended event shows 'Happening now' forever (past event still flagged live)

An event with no end time keeps showing the "HAPPENING NOW" badge long after it has passed. An event dated May 31 · 7:00 PM is listed under "Past" but still shows "HAPPENING NOW". **Expected:** "Happening now" should only show while the event is actually in progress. An open-ended (no end time) event should stop being "happening now" — e.g. treat it as ended after a sensible default duration, or once its start date has clearly passed. **Where:** Event listing / event card — the "HAPPENING NOW" status badge. **Steps to reproduce:** 1. Have an event with a start time but no end time (open-ended), dated in the past 2. View it in the events list (it appears under "Past") 3. It still shows the "HAPPENING NOW" badge despite being days old