update last seen property when processing listings to refresh data

crawler/repositories/listing_repository.py

@@ -193,3 +193,12 @@ class ListingRepository:
             )
 
         return model_listing
+
+    async def mark_seen(self, listing_id: int) -> None:
+        listings = await self.get_listings(only_ids=[listing_id])
+        if len(listings) == 0:
+            return
+        listing = listings[0]
+        now = datetime.now()
+        listing.last_seen = now
+        await self.upsert_listings([listing])