Find videos to fetch based on cast instead of title

vivaweb.go

@@ -208,7 +208,7 @@ func (w *WebClient) FetchVideoMetadata(db *sql.DB) error {
 	log.Printf("Fetching video metadata...")
 	for {
 		// Fetch the next record from the database
-		row := db.QueryRow("select id, url from videos where title is null limit 1")
+		row := db.QueryRow("select id, url from videos where cast is null limit 1")
 		var id int
 		var href string
 		err := row.Scan(&id, &href)