feat: add actor user column to events and dashboard tables

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/api/v1/events.py

@@ -179,19 +179,9 @@ def get_event(
     )
     if event is None:
         raise HTTPException(status_code=404, detail="Event not found")
+    base = event_to_summary(event)
     return EventDetail(
-        id=event.id,
-        event_id=event.event_id,
-        host_id=event.host_id,
-        hostname=event.host.hostname,
-        display_name=event.host.display_name,
-        occurred_at=event.occurred_at,
-        received_at=event.received_at,
-        category=event.category,
-        type=event.type,
-        severity=event.severity,
-        title=event.title,
-        summary=event.summary,
+        **base.model_dump(),
         details=event.details,
         raw=event.raw,
         dedup_key=event.dedup_key,