refactor(item): improves top people display logic

Improves the logic for displaying the top people in the item sections.

The previous implementation simply sliced the people array which
could result in duplicate people being displayed.

This change ensures that the top people displayed are unique by
filtering duplicates based on their id, limiting the number of
displayed people to three.

components/item/ItemPeopleSections.tsx

@@ -37,7 +37,18 @@ export const ItemPeopleSections: React.FC<Props> = ({ item, ...props }) => {
     return { ...item, People: people } as BaseItemDto;
   }, [item, people]);
 
-  const topPeople = useMemo(() => people.slice(0, 3), [people]);
+  const topPeople = useMemo(() => {
+    const seen = new Set<string>();
+    const unique: BaseItemPerson[] = [];
+    for (const person of people) {
+      if (person.Id && !seen.has(person.Id)) {
+        seen.add(person.Id);
+        unique.push(person);
+      }
+      if (unique.length >= 3) break;
+    }
+    return unique;
+  }, [people]);
 
   const renderActorSection = useCallback(
     (person: BaseItemPerson, idx: number, total: number) => {