Add price extraction and validate URL structure in parsers

Added price field to Item struct in AisleGopher and implemented logic to extract price data. Updated Wegmans parser to validate URL structure by ensuring the second segment is "product". These changes improve data accuracy and error handling.

sites/wegmans/wegmans.go

@@ -53,6 +53,10 @@ func (c Config) GetItemPrice(ctx context.Context, b extractor.Browser, u *url.UR
 		return Item{}, ErrInvalidURL
 	}
 
+	if a[1] != "product" {
+		return Item{}, ErrInvalidURL
+	}
+
 	id, _ := strconv.Atoi(a[2])
 
 	if id == 0 {