Feat: Filter the query variable drop-down box options by type #3221 (#8485)

### What problem does this PR solve?

Feat: Filter the query variable drop-down box options by type #3221

### Type of change


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

web/src/pages/flow/constant.tsx

@@ -639,7 +639,16 @@ export const initialEmailValues = {
 export const initialIterationValues = {
   delimiter: ',',
 };
-export const initialIterationStartValues = {};
+export const initialIterationStartValues = {
+  outputs: {
+    item: {
+      type: 'unkown',
+    },
+    index: {
+      type: 'integer',
+    },
+  },
+};
 
 export const initialCodeValues = {
   lang: 'python',

web/src/pages/flow/form/iteration-start-from/index.tsx

@@ -0,0 +1,22 @@
+import { Output, OutputType } from '@/pages/agent/form/components/output';
+import { initialIterationStartValues } from '../../constant';
+
+const outputs = initialIterationStartValues.outputs;
+
+const outputList = Object.entries(outputs).reduce<OutputType[]>(
+  (pre, [key, value]) => {
+    pre.push({ title: key, type: value.type });
+
+    return pre;
+  },
+  [],
+);
+const IterationStartForm = () => {
+  return (
+    <section className="space-y-6 p-4">
+      <Output list={outputList}></Output>
+    </section>
+  );
+};
+
+export default IterationStartForm;