Feat: Delete the agent and tool nodes downstream of the agent node #3221 (#8450)

### What problem does this PR solve?

Feat: Delete the agent and tool nodes downstream of the agent node #3221

### Type of change


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

web/src/pages/agent/utils/delete-node.ts

@@ -0,0 +1,34 @@
+import { Edge } from '@xyflow/react';
+import { filterAllDownstreamAgentAndToolNodeIds } from './filter-downstream-nodes';
+
+// Delete all downstream agent and tool operators of the current agent operator
+export function deleteAllDownstreamAgentsAndTool(
+  nodeId: string,
+  edges: Edge[],
+) {
+  const downstreamAgentAndToolNodeIds = filterAllDownstreamAgentAndToolNodeIds(
+    edges,
+    [nodeId],
+  );
+
+  const downstreamAgentAndToolEdges = downstreamAgentAndToolNodeIds.reduce<
+    Edge[]
+  >((pre, cur) => {
+    const relatedEdges = edges.filter(
+      (x) => x.source === cur || x.target === cur,
+    );
+
+    relatedEdges.forEach((x) => {
+      if (!pre.some((y) => y.id !== x.id)) {
+        pre.push(x);
+      }
+    });
+
+    return pre;
+  }, []);
+
+  return {
+    downstreamAgentAndToolNodeIds,
+    downstreamAgentAndToolEdges,
+  };
+}

web/src/pages/agent/utils/filter-downstream-nodes.ts

@@ -0,0 +1,31 @@
+import { Edge } from '@xyflow/react';
+import { NodeHandleId } from '../constant';
+
+// Get all downstream agent operators of the current agent operator
+export function filterAllDownstreamAgentAndToolNodeIds(
+  edges: Edge[],
+  nodeIds: string[],
+) {
+  return nodeIds.reduce<string[]>((pre, nodeId) => {
+    const currentEdges = edges.filter(
+      (x) =>
+        x.source === nodeId &&
+        (x.sourceHandle === NodeHandleId.AgentBottom ||
+          x.sourceHandle === NodeHandleId.Tool),
+    );
+
+    const downstreamNodeIds: string[] = currentEdges.map((x) => x.target);
+
+    const ids = downstreamNodeIds.concat(
+      filterAllDownstreamAgentAndToolNodeIds(edges, downstreamNodeIds),
+    );
+
+    ids.forEach((x) => {
+      if (pre.every((y) => y !== x)) {
+        pre.push(x);
+      }
+    });
+
+    return pre;
+  }, []);
+}