feat: Add AI tool building capabilities (#7336)

Github issue / Community forum post (link here to close automatically):
https://community.n8n.io/t/langchain-memory-chat/23733

---------

Signed-off-by: Oleg Ivaniv <me@olegivaniv.com>
Co-authored-by: Oleg Ivaniv <me@olegivaniv.com>
Co-authored-by: Val <68596159+valya@users.noreply.github.com>
Co-authored-by: Alex Grozav <alex@grozav.com>
Co-authored-by: कारतोफ्फेलस्क्रिप्ट™ <aditya@netroy.in>
Co-authored-by: Deborah <deborah@starfallprojects.co.uk>
Co-authored-by: Jesper Bylund <mail@jesperbylund.com>
Co-authored-by: Jon <jonathan.bennetts@gmail.com>
Co-authored-by: Michael Kret <88898367+michael-radency@users.noreply.github.com>
Co-authored-by: Giulio Andreini <andreini@netseven.it>
Co-authored-by: Mason Geloso <Mason.geloso@gmail.com>
Co-authored-by: Mason Geloso <hone@Masons-Mac-mini.local>
Co-authored-by: Mutasem Aldmour <mutasem@n8n.io>

packages/@n8n/nodes-langchain/nodes/tools/ToolWikipedia/ToolWikipedia.node.ts

@@ -0,0 +1,50 @@
+/* eslint-disable n8n-nodes-base/node-dirname-against-convention */
+import {
+	NodeConnectionType,
+	type IExecuteFunctions,
+	type INodeType,
+	type INodeTypeDescription,
+	type SupplyData,
+} from 'n8n-workflow';
+import { WikipediaQueryRun } from 'langchain/tools';
+import { logWrapper } from '../../../utils/logWrapper';
+import { getConnectionHintNoticeField } from '../../../utils/sharedFields';
+
+export class ToolWikipedia implements INodeType {
+	description: INodeTypeDescription = {
+		displayName: 'Wikipedia',
+		name: 'toolWikipedia',
+		icon: 'file:wikipedia.svg',
+		group: ['transform'],
+		version: 1,
+		description: 'Search in Wikipedia',
+		defaults: {
+			name: 'Wikipedia',
+		},
+		codex: {
+			categories: ['AI'],
+			subcategories: {
+				AI: ['Tools'],
+			},
+			resources: {
+				primaryDocumentation: [
+					{
+						url: 'https://docs.n8n.io/integrations/builtin/cluster-nodes/sub-nodes/n8n-nodes-langchain.toolwikipedia/',
+					},
+				],
+			},
+		},
+		// eslint-disable-next-line n8n-nodes-base/node-class-description-inputs-wrong-regular-node
+		inputs: [],
+		// eslint-disable-next-line n8n-nodes-base/node-class-description-outputs-wrong
+		outputs: [NodeConnectionType.AiTool],
+		outputNames: ['Tool'],
+		properties: [getConnectionHintNoticeField([NodeConnectionType.AiAgent])],
+	};
+
+	async supplyData(this: IExecuteFunctions): Promise<SupplyData> {
+		return {
+			response: logWrapper(new WikipediaQueryRun(), this),
+		};
+	}
+}