[Bug] Zookeeper lock leaks after deleting the engine.

### Code of Conduct

- [x] I agree to follow this project's [Code of Conduct](https://www.apache.org/foundation/policies/conduct)

### Search before asking

- [x] I have searched in the [issues](https://github.com/apache/kyuubi/issues?q=is%3Aissue) and found no similar issues.

### Describe the bug

After deleting a Spark engine, the lock path for that engine is not removed. This causes accumulating znodes for the lock.
```shell
# create cluster cluster-20250610024214-ha03nplj
[zk: localhost:2181(CONNECTED) 5] ls /kyuubi_1.8.0-SNAPSHOT_GROUP_SPARK_SQL/group1/cluster-20250610024214-ha03nplj
[serviceUri=192.168.56.10:36601;version=1.8.0-SNAPSHOT;spark.driver.memory=10g;spark.executor.memory=10g;kyuubi.engine.id=spark-c58207333fd740ceab863ad5785790c6;kyuubi.engine.url=192.168.56.10:4040;refId=dd58a01c-77db-44e3-b02c-9ad99c254c39;sequence=0000000000]
[zk: localhost:2181(CONNECTED) 6] ls /kyuubi_1.8.0-SNAPSHOT_GROUP_SPARK_SQL_lock/group1/cluster-20250610024214-ha03nplj
[leases, locks]
# delete cluster cluster-20250610024214-ha03nplj
[zk: localhost:2181(CONNECTED) 7] ls /kyuubi_1.8.0-SNAPSHOT_GROUP_SPARK_SQL/group1/cluster-20250610024214-ha03nplj
[]
[zk: localhost:2181(CONNECTED) 8] ls /kyuubi_1.8.0-SNAPSHOT_GROUP_SPARK_SQL_lock/group1/cluster-20250610024214-ha03nplj
[leases, locks]
```

### Affects Version(s)

1.8.0

### Kyuubi Server Log Output

```logtalk

```

### Kyuubi Engine Log Output

```logtalk

```

### Kyuubi Server Configurations

```yaml

```

### Kyuubi Engine Configurations

```yaml

```

### Additional context

_No response_

### Are you willing to submit PR?

- [ ] Yes. I would be willing to submit a PR with guidance from the Kyuubi community to fix.
- [x] No. I cannot submit a PR at this time.

Reproduce the issue using the ZooKeeper paths and deletion sequence shown in the report. Trace the Spark engine deletion flow and the corresponding lock-path cleanup, then verify that deleting an engine removes its lock znodes and that repeated deletions do not leave accumulating paths.

Written by the indexing model from the issue text.