Sort CheapShark deals by recency instead of deal rating

The bot polls periodically for new deals, but sorting by "Deal Rating"
meant it always returned the same top-rated deals and would never
discover new listings that aren't in the top 10 by rating. Sorting by
"recent" ensures newly added or updated deals are seen on each poll.

https://claude.ai/code/session_017eMsVwUopgmnEyd6JJedpV

gaming_deals_bot/cheapshark.py

@@ -55,7 +55,7 @@ async def fetch_deals(
     params = {
         "storeID": store_ids,
         "upperPrice": str(int(max_price)),
-        "sortBy": "Deal Rating",
+        "sortBy": "recent",
         "desc": "1",
         "pageSize": str(page_size),
     }