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

index.html

@@ -1318,6 +1318,6 @@
     </div>
 </div>
 
-<script src="assets/js/app.js?v=20260504b"></script>
+<script src="assets/js/app.js?v=20260504c"></script>
 </body>
 </html>