feat: Enhance space hierarchy management by implementing asynchronous room fetching and improving room handling logic

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

@@ -339,6 +339,7 @@ export function Space() {
   // Forum feed unless user opened manage, search, or a room (not tied to URL alias encoding).
   const feedActive = isForum && !lobbySelected && !searchSelected && !selectedRoomId;
   const showForumFeedSidebar = feedActive;
+  const forumManageMode = isForum && lobbySelected;
 
   if (showForumFeedSidebar) {
     return (
@@ -351,6 +352,14 @@ export function Space() {
     );
   }
 
+  if (forumManageMode) {
+    return (
+      <PageNav>
+        <SpaceHeader />
+      </PageNav>
+    );
+  }
+
   const spacePath = getCanonicalAliasOrRoomId(mx, space.roomId);
 
   return (