fix: Change listType from SINGLE_SELECT to PRODUCT_LIST to match pastorini

Error 479 was still occurring even with legacy listMessage format.
The issue is that listType must be PRODUCT_LIST (not SINGLE_SELECT)
to match the biz node type="product_list" v="2" that we're injecting.

This matches pastorini's working implementation exactly:
- listMessage with listType: PRODUCT_LIST
- biz node with type="product_list" v="2"

https://claude.ai/code/session_01Vgu4xrsj8aUVCHWb4pmQPF

src/Utils/messages.ts

@@ -1020,7 +1020,7 @@ export const generateListMessageLegacy = (
 			description,
 			buttonText,
 			footerText: footer,
-			listType: WAProto.Message.ListMessage.ListType.SINGLE_SELECT,
+			listType: WAProto.Message.ListMessage.ListType.PRODUCT_LIST,
 			sections: listInfo.sections.map(section => ({
 				title: section.title,
 				rows: section.rows.map(row => ({