Add document resource to n8n node and MCP sendSigningNotifications tool

Add a complete document resource to the n8n node with 21 operations
covering documents, versions, and signatures — matching the MCP
specification. Also add the sendSigningNotifications tool to the MCP
API for triggering pending signature reminders.

n8n operations: create, get, getAll, update, delete, archive,
unarchive, getVersion, getAllVersions, createDraftVersion,
updateVersion, deleteDraftVersion, publishMajorVersion,
publishMinorVersion, requestApproval, voidApproval, getSignature,
getAllSignatures, requestSignature, cancelSignature,
sendSigningNotifications.

Signed-off-by: Sacha Al Himdani <sacha@getprobo.com>

packages/n8n-node/nodes/Probo/actions/document/getVersion.operation.ts

@@ -0,0 +1,68 @@
+// Copyright (c) 2025-2026 Probo Inc <hello@getprobo.com>.
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+import type { INodeProperties, IExecuteFunctions, INodeExecutionData } from 'n8n-workflow';
+import { proboApiRequest } from '../../GenericFunctions';
+
+export const description: INodeProperties[] = [
+	{
+		displayName: 'Document Version ID',
+		name: 'documentVersionId',
+		type: 'string',
+		displayOptions: {
+			show: {
+				resource: ['document'],
+				operation: ['getVersion'],
+			},
+		},
+		default: '',
+		description: 'The ID of the document version',
+		required: true,
+	},
+];
+
+export async function execute(
+	this: IExecuteFunctions,
+	itemIndex: number,
+): Promise<INodeExecutionData> {
+	const documentVersionId = this.getNodeParameter('documentVersionId', itemIndex) as string;
+
+	const query = `
+		query GetDocumentVersion($documentVersionId: ID!) {
+			node(id: $documentVersionId) {
+				... on DocumentVersion {
+					id
+					title
+					major
+					minor
+					status
+					content
+					changelog
+					classification
+					documentType
+					publishedAt
+					createdAt
+					updatedAt
+				}
+			}
+		}
+	`;
+
+	const responseData = await proboApiRequest.call(this, query, { documentVersionId });
+
+	return {
+		json: responseData,
+		pairedItem: { item: itemIndex },
+	};
+}