fix(i18n): translate antiwaste title in IT/DE + use quantity validation

- translations: antiwaste.title = 'Rapporto Anti-Spreco' (IT), 'Anti-Verschwendungs-Bericht' (DE)
- translations: add use.error_exceeds_stock in IT/EN/DE
- submitUse(): block submit if qty > available at selected location + shake animation
- adjustUseQty(): cap '+' button at max available at selected location (incl. sub-unit mode)
- style.css: add @keyframes inputShake + .input-shake class

Bump app.js cache buster to v=20260504c

translations/en.json

@@ -241,7 +241,8 @@
         "toast_bring": "🛒 Product finished → added to Bring!",
         "toast_opened_finished": "🔓 Opened package of {name} finished!",
         "disambiguation_hint": "What do you mean by \"all done\"?",
-        "disambiguation_all": "🗑️ Finish EVERYTHING ({qty})"
+        "disambiguation_all": "🗑️ Finish EVERYTHING ({qty})",
+        "error_exceeds_stock": "⚠️ You cannot use more than you have available!"
     },
     "product": {
         "title_new": "New Product",