### CI Link

https://gradle-enterprise.elastic.co/s/sa7kgcpbjsuyo

### Repro line

./gradlew ':x-pack:plugin:esql:internalClusterTest' --tests "org.elasticsearch.xpack.esql.action.EsqlActionTaskIT.testCancelRead" -Dtests.seed=A10FD59C7183AD95 -Dbuild.snapshot=false -Dtests.jvm.argline="-Dbuild.snapshot=false" -Dtests.locale=ga-IE -Dtests.timezone=Europe/Stockholm -Druntime.java=20

### Does it reproduce?

No

### Applicable branches

main

### Failure history

_No response_

### Failure excerpt

```
org.elasticsearch.xpack.esql.action.EsqlActionTaskIT > testCancelRead FAILED
    java.lang.AssertionError: 
    Expected: a collection with size <2>
         but: collection size was <0>
        at __randomizedtesting.SeedInfo.seed([A10FD59C7183AD95:34226718C99014F4]:0)
        at org.hamcrest.MatcherAssert.assertThat(MatcherAssert.java:18)
        at org.junit.Assert.assertThat(Assert.java:956)
        at org.junit.Assert.assertThat(Assert.java:923)
        at org.elasticsearch.xpack.esql.action.EsqlActionTaskIT.lambda$getTasksStarting$2(EsqlActionTaskIT.java:229)
        at org.elasticsearch.test.ESTestCase.assertBusy(ESTestCase.java:1196)
        at org.elasticsearch.test.ESTestCase.assertBusy(ESTestCase.java:1169)
        at org.elasticsearch.xpack.esql.action.EsqlActionTaskIT.getTasksStarting(EsqlActionTaskIT.java:221)
        at org.elasticsearch.xpack.esql.action.EsqlActionTaskIT.testCancelRead(EsqlActionTaskIT.java:167)
```
x-pack/plugin/esql/compute/src/main/java/org/elasticsearch/compute/lucene/LuceneOperator.java
return ENTRY.name;
        }
        public int currentLeaf() {
            return processedSlices;
        }
        public int totalLeaves() {
            return totalSlices;
        }
        public int pagesEmitted() {
            return pagesEmitted;
        }
        public int slicePosition() {
            return slicePosition;
        }
        public int sliceSize() {
            return sliceSize;
        }
        @Override
        public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
            builder.startObject();
            builder.field("processed_sliced", processedSlices);
            builder.field("total_slices", totalSlices);
            builder.field("slice_position", slicePosition);
            builder.field("slice_size", sliceSize);
            builder.field("pages_emitted", pagesEmitted);
            return builder.endObject();
        }
        @Override
        public boolean equals(Object o) {
            if (this == o) return true;