fix: correctly track hasUnsavedChanges when only 1 pending change remains

src/App.tsx

@@ -281,7 +281,7 @@ export default function App() {
     setAppState(prev => {
       const newData = [...prev.data];
       newData[pending.rowIndex] = pending.originalData;
-      const stillPending = Object.keys(pendingRows).length > 1;
+      const stillPending = Object.keys(pendingRows).length > 0;
       return { ...prev, data: newData, hasUnsavedChanges: stillPending };
     });
     setPendingRows(prev => { const n = { ...prev }; delete n[articleNo]; return n; });