feat(workflow): enhance group node availability checks

- Updated `checkMakeGroupAvailability` to include a check for existing group nodes, preventing group creation if a group node is already selected.
- Modified `useMakeGroupAvailability` and `useNodesInteractions` hooks to incorporate the new group node check, ensuring accurate group creation logic.
- Adjusted UI rendering logic in the workflow panel to conditionally display elements based on node type, specifically for group nodes.

web/app/components/workflow/nodes/_base/components/workflow-panel/index.tsx

@@ -594,7 +594,7 @@ const BasePanel: FC<BasePanelProps> = ({
             )
           }
           {
-            !needsToolAuth && !currentDataSource && !currentTriggerPlugin && (
+            !needsToolAuth && !currentDataSource && !currentTriggerPlugin && data.type !== BlockEnum.Group && (
               <div className="flex items-center justify-between pl-4 pr-3">
                 <Tab
                   value={tabType}
@@ -603,9 +603,9 @@ const BasePanel: FC<BasePanelProps> = ({
               </div>
             )
           }
-          <Split />
+          {data.type !== BlockEnum.Group && <Split />}
         </div>
-        {tabType === TabType.settings && (
+        {(tabType === TabType.settings || data.type === BlockEnum.Group) && (
           <div className="flex flex-1 flex-col overflow-y-auto">
             <div>
               {cloneElement(children as any, {