feat(workflow): add altenate merge tool and translate workflow node and engine errors across locales

src/js/workflow/nodes/timestamp-node.ts

@@ -3,6 +3,7 @@ import { BaseWorkflowNode } from './base-node';
 import { pdfSocket } from '../sockets';
 import type { SocketData } from '../types';
 import { requirePdfInput, processBatch } from '../types';
+import { wfError } from '../errors';
 import { TIMESTAMP_TSA_PRESETS } from '../../config/timestamp-tsa.js';
 import { timestampPdf } from '../../logic/digital-sign-pdf.js';
 import { loadPdfDocument } from '../../utils/load-pdf-document.js';
@@ -47,8 +48,9 @@ export class TimestampNode extends BaseWorkflowNode {
         try {
           bytes = await timestampPdf(input.bytes, tsaUrl);
         } catch (err) {
+          const message = err instanceof Error ? err.message : String(err);
           throw new Error(
-            `Failed to timestamp using TSA ${tsaUrl}: ${err instanceof Error ? err.message : err}`,
+            wfError('timestampFailed', { tsa: tsaUrl, message }),
             { cause: err }
           );
         }