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 });
       }
     };
 

src/app/pages/client/space/Space.tsx

@@ -470,9 +470,6 @@ export function Space() {
           items.push({ type: 'subroom', roomId: subRoomId, room: subRoom, depth: baseDepth + 1, isLast });
           // Recursively add sub-rooms of sub-rooms
           addSubRooms(subRoomId, baseDepth + 1);
-        } else {
-          // Unjoined sub-room - show with join button
-          items.push({ type: 'unjoined-subroom', roomId: subRoomId, depth: baseDepth + 1, isLast });
         }
       });
     };