### Elasticsearch Version

main

### Installed Plugins

_No response_

### Java Version

_bundled_

### OS Version

all

### Problem Description

Do this

### Steps to Reproduce

```
rm /tmp/evil
for a in {0..9}; do
   for b in {0..9}; do
      echo '{"index": {}}' >> /tmp/evil
      echo '{"a": '$a', "b": '$b'}' >> /tmp/evil
   done
done
echo >> /tmp/evil

curl -uelastic:password -XDELETE localhost:9200/test
curl -HContent-Type:application/json -uelastic:password -XPUT localhost:9200/test
curl -HContent-Type:application/json -uelastic:password -XPOST localhost:9200/test/_bulk --data-binary @/tmp/evil
curl -HContent-Type:application/json -uelastic:password -XPOST localhost:9200/test/_forcemerge?max_num_segments=1
curl -HContent-Type:application/json -uelastic:password -XPOST localhost:9200/test/_refresh

curl -HContent-Type:application/json -uelastic:password -XPOST localhost:9200/_esql?pretty -d'{
   "query": "FROM test | STATS MAX(a) BY a, b | KEEP a"
}'
```

### Logs (if relevant)

_No response_
x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/planner/LocalExecutionPlanner.java
Layout.ChannelSet outputSet = inputChannelToOutputIds.get(inChannel);
            if (outputSet != null) {
                mask.set(inChannel);
                layout.append(outputSet);
            }
        }
        if (mask.cardinality() == source.layout.numberOfChannels()) {
            
            return source.with(layout.build());
        } else {
            return source.with(new ProjectOperatorFactory(mask), layout.build());
        }
    }
    private PhysicalOperation planFilter(FilterExec filter, LocalExecutionPlannerContext context) {
        PhysicalOperation source = plan(filter.child(), context);
        
        return source.with(new FilterOperatorFactory(toEvaluator(filter.condition(), source.layout)), source.layout);
    }
    private PhysicalOperation planLimit(LimitExec limit, LocalExecutionPlannerContext context) {
        PhysicalOperation source = plan(limit.child(), context);
        return source.with(new Factory((Integer) limit.limit().fold()), source.layout);
    }
    private PhysicalOperation planMvExpand(MvExpandExec mvExpandExec, LocalExecutionPlannerContext context) {
        PhysicalOperation source = plan(mvExpandExec.child(), context);
        return source.with(new MvExpandOperator.Factory(source.layout.get(mvExpandExec.target().id()).channel()), source.layout);
    }
    /**
     * Immutable physical operation.
     */
    public static class PhysicalOperation implements Describable {