fix(orders): back button links to Vydané tab, not the nonexistent /orders/issued

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/admin/pages/IssuedOrderDetail.tsx

@@ -823,7 +823,7 @@ export default function IssuedOrderDetail() {
         <Box sx={{ display: "flex", alignItems: "center", gap: 2 }}>
           <Button
             component={RouterLink}
-            to="/orders/issued"
+            to="/orders?tab=vydane"
             variant="outlined"
             color="inherit"
             startIcon={BackIcon}