Feat: Display the selected variables in the variable aggregation node. #10427 (#11113)

### What problem does this PR solve?
Feat: Display the selected variables in the variable aggregation node.
#10427

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

web/src/pages/agent/hooks/use-build-structured-output.ts

@@ -153,3 +153,24 @@ export function useFindAgentStructuredOutputTypeByValue() {
 
   return findAgentStructuredOutputTypeByValue;
 }
+
+export function useFindAgentStructuredOutputLabelByValue() {
+  const { getNode } = useGraphStore((state) => state);
+
+  const findAgentStructuredOutputLabel = useCallback(
+    (value?: string) => {
+      if (value) {
+        const operatorName = getNode(getNodeId(value ?? ''))?.data.name;
+
+        if (operatorName) {
+          return operatorName + ' / ' + value?.split('@').at(1);
+        }
+      }
+
+      return '';
+    },
+    [getNode],
+  );
+
+  return findAgentStructuredOutputLabel;
+}