Range scan does not produce keys in ordered format

[arriqaaq]

Issue Description

Range scan on vart does not produce ordered keys on bulk_insert based on this test. Current fix is to order keys before writing to the index.

    #[tokio::test]
    async fn scan_multiple_keys_within_single_transaction() {
        let (store, _) = create_store(false);
        // Define key-value pairs for the test
        let keys_to_insert = vec![
            Bytes::from("test1"),
            Bytes::from("test2"),
            Bytes::from("test3"),
        ];

        let mut txn = store.begin().unwrap();
        for key in &keys_to_insert {
            txn.set(key, key).unwrap();
        }
        txn.commit().await.unwrap();

        let range = "test1".as_bytes()..="test7".as_bytes();

        let txn = store.begin().unwrap();
        let results = txn.scan(range, None).unwrap();
        assert_eq!(results.len(), 3);
        assert_eq!(results[0].0, keys_to_insert[0]);
        assert_eq!(results[1].0, keys_to_insert[1]);
        assert_eq!(results[2].0, keys_to_insert[2]);
        assert_eq!(results[0].1, keys_to_insert[0]);
        assert_eq!(results[1].1, keys_to_insert[1]);
        assert_eq!(results[2].1, keys_to_insert[2]);
    }