feat(SearXNG Node): Add SearXNG tool (#13218)

packages/@n8n/nodes-langchain/credentials/SearXngApi.credentials.ts

@@ -0,0 +1,19 @@
+import type { ICredentialType, INodeProperties } from 'n8n-workflow';
+
+export class SearXngApi implements ICredentialType {
+	name = 'searXngApi';
+
+	displayName = 'SearXNG';
+
+	documentationUrl = 'searxng';
+
+	properties: INodeProperties[] = [
+		{
+			displayName: 'API URL',
+			name: 'apiUrl',
+			type: 'string',
+			default: '',
+			required: true,
+		},
+	];
+}