feat: cena pre appkacov ({cena_app}), tag cenovky pre appkacov, doplnkove grafiky ako stitky

- premenna {cena_app} v cenovke a pole Pre appkacov v produkte (ked ju sablona pouziva)
- tag Appka v sablone; import da cenovku pre appkacov produktom s Cenou pre appkacov,
  bezny produkt ju nikdy nedostane
- stlpec Doplnkove grafiky sa pri importe zmeni na stitky na fotke

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/lib/productCard.ts

@@ -205,7 +205,7 @@ export function cardVisualKey(p: CardProduct, ctx: CardContext): string {
     p.customBadgePngUrl, badgeWidthFor(p, ctx.variant),
     t ? [t.svgRaw, t.layersConfig, t.width] : null,
     p.priceMain, p.priceSub, p.discountText, p.badgeText, p.unitPrice,
-    p.cardPriceMain, p.cardPriceSub, p.cardDiscount, p.cardUnitPrice,
+    p.cardPriceMain, p.cardPriceSub, p.cardDiscount, p.cardUnitPrice, p.appPriceMain, p.appPriceSub,
     p.noCardPriceMain, p.noCardPriceSub, p.noCardDiscount, p.noCardUnitPrice,
     p.stores, p.storesOffsetX ?? DEFAULT_STORES_OFFSET_X, p.storesOffsetY ?? DEFAULT_STORES_OFFSET_Y, p.storesSize ?? DEFAULT_STORES_SIZE,
     p.labels || [], p.extraPhotos || [], photoStack(p)
@@ -339,6 +339,9 @@ function renderVisualPreview(p: CardProduct, ctx: CardContext, key: string): str
     </div>`;
 }
 
+// Šablóna cenovky zobrazuje cenu pre appkáčov
+export const usesAppPrice = (t?: BadgeTemplate) => !!t && JSON.stringify(t.layersConfig || []).includes('{cena_app}');
+
 // Alt text obrázka karty: názov, gramáž a cena (ako v šablóne); ručne zadaný alt má prednosť
 export function productCardAlt(p: CardProduct, variant: CardVariant): string {
   const name = [pickAlt(p.title), p.quantity].filter(Boolean).join(' ');
@@ -355,9 +358,11 @@ export function productCardAlt(p: CardProduct, variant: CardVariant): string {
   } else {
     const main = price(p.priceMain, p.priceSub);
     const card = price(p.cardPriceMain, p.cardPriceSub);
+    const app = usesAppPrice(p.badgeCustomTemplate) ? price(p.appPriceMain, p.appPriceSub) : '';
     priceText = [
       main ? `${main}${p.discountText ? `, zľava ${pct(p.discountText)}` : ''}` : '',
-      card ? `s kartou ${card}${p.cardDiscount ? ` (zľava ${pct(p.cardDiscount)})` : ''}` : ''
+      card ? `s kartou ${card}${p.cardDiscount ? ` (zľava ${pct(p.cardDiscount)})` : ''}` : '',
+      app ? `v aplikácii ${app}` : ''
     ].filter(Boolean).join(', ');
   }
   return pickAlt(p.imageAlt, [name, priceText].filter(Boolean).join(' – '), 'Produkt');