fix: clicking Applications header navigates back to all apps

When the Applications section is already expanded, clicking the
header now navigates to /{tab} (all applications) instead of
collapsing. When collapsed, clicking expands as before.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/src/components/LayoutShell.tsx

@@ -327,11 +327,14 @@ function LayoutContent() {
       navigate('/exchanges');
       return;
     }
-    setAppsOpen((prev) => {
-      writeCollapsed(SK_APPS, !prev);
-      return !prev;
-    });
-  }, [isAdminPage, navigate]);
+    if (appsOpen) {
+      // Already open — navigate to all applications
+      navigate(`/${scope.tab}`);
+    } else {
+      setAppsOpen(true);
+      writeCollapsed(SK_APPS, true);
+    }
+  }, [isAdminPage, appsOpen, navigate, scope.tab]);
 
   const toggleAdmin = useCallback(() => {
     if (!isAdminPage) {