fix(merge): page labels, retain-labels option, and workflow alignment with cpdf

src/js/logic/pdf-workflow-page.ts

@@ -1286,6 +1286,7 @@ function showNodeSettings(node: BaseWorkflowNode) {
     'subsetFonts',
     'convertToGrayscale',
     'removeThumbnails',
+    'retainPageLabels',
   ]);
   const multiSelectDropdowns = new Set(['language']);
   const advancedControls = new Set(['resolution', 'binarize', 'whitelist']);
@@ -1307,6 +1308,8 @@ function showNodeSettings(node: BaseWorkflowNode) {
     y0: 'Top edge in points',
     x1: 'Right edge in points',
     y1: 'Bottom edge in points',
+    retainPageLabels:
+      "Off (default): natural 1–N numbering. On: each file's original page labels are preserved (may produce duplicate labels).",
   };
 
   const inputClass =