Docs: Fix deprecated initialize agent in ainetwork (#30355)

## Description
- Replaced `initialize_agent`, `AgentType` usage in ainetwork
integration
- Updated usage example to `create_react_agent` in langgraph

## Issue
- #29277

## Dependencies
- N/A

## Twitter handler
- I don't use Twitter

docs/docs/integrations/tools/ainetwork.ipynb

@@ -130,16 +130,11 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "from langchain.agents import AgentType, initialize_agent\n",
     "from langchain_openai import ChatOpenAI\n",
+    "from langgraph.prebuilt import create_react_agent\n",
     "\n",
     "llm = ChatOpenAI(temperature=0)\n",
-    "agent = initialize_agent(\n",
-    "    tools=tools,\n",
-    "    llm=llm,\n",
-    "    verbose=True,\n",
-    "    agent=AgentType.OPENAI_FUNCTIONS,\n",
-    ")"
+    "agent = create_react_agent(model=llm, tools=tools)"
    ]
   },
   {
@@ -199,8 +194,10 @@
    ],
    "source": [
     "print(\n",
-    "    agent.run(\n",
-    "        f\"Create an app in the AINetwork Blockchain database with the name {appName}\"\n",
+    "    agent.invoke(\n",
+    "        {\n",
+    "            \"messages\": f\"Create an app in the AINetwork Blockchain database with the name {appName}\"\n",
+    "        }\n",
     "    )\n",
     ")"
    ]