Add page number display to StepGridReview summary bar

The page_number was only shown in GridEditor.tsx (ocr-overlay) but
the OCR pipeline uses StepGridReview.tsx which has its own summary bar.
Display the extracted page number (e.g. "S. 233") next to the
dictionary detection badge.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

admin-lehrer/components/ocr-pipeline/StepGridReview.tsx

@@ -235,6 +235,11 @@ export function StepGridReview({ sessionId, onNext, saveRef }: StepGridReviewPro
             Woerterbuch ({Math.round(grid.dictionary_detection.confidence * 100)}%)
           </span>
         )}
+        {grid.page_number?.text && (
+          <span className="px-1.5 py-0.5 rounded bg-gray-100 dark:bg-gray-700 text-gray-600 dark:text-gray-300 border border-gray-200 dark:border-gray-600">
+            S. {grid.page_number.number ?? grid.page_number.text}
+          </span>
+        )}
         {lowConfCells.length > 0 && (
           <span className="px-2 py-0.5 rounded-full bg-red-50 dark:bg-red-900/20 text-red-600 dark:text-red-400 border border-red-200 dark:border-red-800">
             {lowConfCells.length} niedrige Konfidenz