docs: add docs for vectara tools (#30958)

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- [ ] **Docs for Vectara Tools**: "langchain-vectara"

docs/docs/integrations/providers/vectara.ipynb

@@ -315,6 +315,17 @@
     "Vectara offers Intelligent Query Rewriting option which  enhances search precision by automatically generating metadata filter expressions from natural language queries. This capability analyzes user queries, extracts relevant metadata filters, and rephrases the query to focus on the core information need. For more details [go to this notebook](../retrievers/self_query/vectara_self_query.ipynb)."
    ]
   },
+  {
+   "cell_type": "markdown",
+   "source": [
+    "## Vectara tools\n",
+    "Vectara provides serval tools that can be used with Langchain. For more details [go to this notebook](../tools/vectara.ipynb)"
+   ],
+   "metadata": {
+    "collapsed": false
+   },
+   "id": "beadf6f485c1a69"
+  },
   {
    "cell_type": "code",
    "execution_count": null,