fix(amazon-shopping): verify prime and delivery filters

skills/amazon-shopping/src/detail-page.ts

@@ -76,15 +76,42 @@ function extractHistogramText(root: HTMLElement): string {
   return parts.join(" ");
 }
 
-function deliveryFromText(text: string): DeliverySummary | undefined {
+function deliveryFromText(text: string, primeSignal = false): DeliverySummary | undefined {
   const display = text.replace(/\s+/g, " ").trim();
   if (!display) {
-    return undefined;
+    return primeSignal ? { display: "Prime delivery available", prime: true } : undefined;
   }
   return {
     display,
     free: /\bfree\b/i.test(display),
-    prime: /\bprime\b/i.test(display)
+    prime: primeSignal || /\bprime\b/i.test(display)
+  };
+}
+
+function hasPrimeSignal(root: HTMLElement): boolean {
+  const attributeText = root.querySelectorAll("[id], [class], [aria-label], img[alt]")
+    .map((node) => [
+      attrOf(node, "id"),
+      attrOf(node, "class"),
+      attrOf(node, "aria-label"),
+      attrOf(node, "alt")
+    ].join(" "))
+    .join(" ");
+  return /a-icon-prime|prime-logo|primeExclusive|primePopover|amazon\s+prime|\bprime\b/i.test(attributeText);
+}
+
+function mergeDelivery(detail: DeliverySummary | undefined, base: DeliverySummary | undefined): DeliverySummary | undefined {
+  if (!detail) {
+    return base;
+  }
+  if (!base) {
+    return detail;
+  }
+  return {
+    display: detail.display || base.display,
+    free: Boolean(detail.free || base.free),
+    prime: Boolean(detail.prime || base.prime),
+    fastestDate: detail.fastestDate ?? base.fastestDate
   };
 }
 
@@ -113,7 +140,7 @@ export function extractDetailPage(html: string, base: ProductSearchResult): Prod
     price: parseMoney(priceText) ?? base.price,
     rating: parseRating(ratingText) ?? base.rating,
     reviewCount: parseReviewCount(reviewText) ?? base.reviewCount,
-    delivery: deliveryFromText(deliveryText) ?? base.delivery,
+    delivery: mergeDelivery(deliveryFromText(deliveryText, hasPrimeSignal(root)), base.delivery),
     availability: availability || base.availability,
     seller: seller || base.seller,
     bullets: extractBullets(root),