feat: remove unjoined sub-room handling from Home and Space components

src/app/pages/client/home/Home.tsx

@@ -291,9 +291,6 @@ export function Home() {
         subRooms.forEach((subRoomId, index) => {
           addRoomAndSubRooms(subRoomId, depth + 1, roomId, index === subRooms.length - 1);
         });
-      } else if (parentId) {
-        // Unjoined sub-room - show with join button
-        items.push({ type: 'unjoined-subroom', roomId, depth, parentId, isLast });
       }
     };