fix(streckkod+kvitto): sparad-bekraftelse, fettvarden, kvitto-antal

Streckkod / produktbidrag:
- Tydlig bekraftelse 'Sparad i delade katalogen - tack!' visas nu efter att en
  fotad produkt lasts av, sa man ser att bidraget gick fram (forut bara
  'Skanna igen' utan aterkoppling).
- Naringsetiketter laser nu ocksa enkelomattat och fleromattat fett (t.ex.
  olivolja visar tre fettrader). Nya valfria falt monounsaturatedFatG/
  polyunsaturatedFatG i NutritionValues + READ_NUTRITION_LABEL + prompt +
  produktpanelen. Obligatoriska EU-falt oforandrade.

Kvitto:
- Rader som ar samma vara (samma normaliserade namn + enhet) slas nu ihop till
  EN vara med ratt antal - '2 x mjolk' pa kvittot blir en vara a 2 st i stallet
  for tva rader a 1 st. Priser summeras, rabatter dras som forut. En kvittorad
  raknas som minst 1 exemplar aven om antal saknas.

Verifierat: typecheck hela repot gront, nutrition-engine 19/19, ai-contracts
24/24, worker 23/23, api 104/104, samt repro mot testdatabas (2 mjolk-rader ->
1 vara a 2; olivolja sparar fett/mattat/enkel-/fleromattat).

apps/mobile/src/locales/en/common.json

@@ -33,6 +33,7 @@
   "barcode.contributing.title": "Reading the package…",
   "barcode.contributing.body": "We're extracting nutrition, allergens and ingredients – and saving the product to the shared catalogue so the next person doesn't have to photograph it.",
   "barcode.contributing.failed": "Couldn't read the package. Try again with a sharp photo and good lighting.",
+  "barcode.contributing.saved": "✓ Saved to the shared catalogue – thanks for contributing!",
   "barcode.contributing.frontDone": "Front photo taken",
   "barcode.contributing.backPrompt": "Now photograph the back with the nutrition label and ingredients – that completes the product.",
   "barcode.contributing.skipBack": "Done, analyse",
@@ -463,6 +464,8 @@
   "barcode.info.sugar": "– of which sugars",
   "barcode.info.fat": "Fat",
   "barcode.info.satfat": "– of which saturates",
+  "barcode.info.monofat": "– of which monounsaturated",
+  "barcode.info.polyfat": "– of which polyunsaturated",
   "barcode.info.fiber": "Fibre",
   "barcode.info.salt": "Salt",
   "barcode.info.allergens": "Allergens",