ux: merge vacuum sealed question into move-after-use modal

Instead of a separate floating prompt after use, the vacuum sealed checkbox
is now shown directly inside the 'where to put the rest?' modal:
- Always shown for container-type units (conf/g/kg/ml/l) or if previously sealed
- Pre-checked when the item was already vacuum sealed (semi-automatic)
- Saving on 'rimani qui' button also persists the vacuum state
- Saves one step: user answers location + vacuum in a single interaction

index.html

@@ -1462,6 +1462,6 @@
     </div>
 </div>
 
-<script src="assets/js/app.js?v=20260510d"></script>
+<script src="assets/js/app.js?v=20260510e"></script>
 </body>
 </html>