Simplify embedded mode navigation to stay within iframe

Remove the complex token-passing logic for new tabs in embedded mode.
Instead, navigation now stays within the iframe for a simpler UX.

- Remove handleNewWindowClick auth handler from sidebar items
- Simplify useNewWindow hook to navigate within iframe when embedded

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

activepieces-fork/packages/react-ui/src/lib/navigation-utils.tsx

@@ -8,24 +8,12 @@ export const useNewWindow = () => {
   const { embedState } = useEmbedding();
   const navigate = useNavigate();
   if (embedState.isEmbedded) {
-    // In embedded mode, open new tab with authentication token
-    return (route: string, searchParams?: string) => {
-      const token = authenticationSession.getToken();
-      const fullRoute = `${route}${searchParams ? '?' + searchParams : ''}`;
-
-      if (token) {
-        // Pass token for auto-authentication in new tab
-        const encodedRedirect = encodeURIComponent(fullRoute);
-        const authUrl = `/authenticate?token=${encodeURIComponent(token)}&redirect=${encodedRedirect}`;
-        window.open(authUrl, '_blank', 'noopener');
-      } else {
-        // Fallback to in-iframe navigation if no token
-        navigate({
-          pathname: route,
-          search: searchParams,
-        });
-      }
-    };
+    // In embedded mode, navigate within the iframe (don't open new tabs)
+    return (route: string, searchParams?: string) =>
+      navigate({
+        pathname: route,
+        search: searchParams,
+      });
   } else {
     return (route: string, searchParams?: string) =>
       window.open(