### Elasticsearch Version

main

### Installed Plugins

_No response_

### Java Version

_bundled_

### OS Version

all

### Problem Description

When you configure an `aggregate_metric_double` with `ignore_malformed: true` and send a malformed value we create an `_ignored` field with three values, `field.value_count`, `field.min`, and `field.max`. This is the only top "composite" field that creates `_ignored` values for its children. Things like shape only create `field` in `_ignored`. Is there a good reason for `aggregate_metric_double` to be different?

### Steps to Reproduce

see above

### Logs (if relevant)

_No response_
x-pack/plugin/mapper-aggregate-metric/src/main/java/org/elasticsearch/xpack/aggregatemetric/mapper/AggregateDoubleMetricFieldMapper.java
for (Iterator<IndexableField> iter = context.doc().getFields().iterator(); iter.hasNext();) {
                    IndexableField field = iter.next();
                    if (ignoreFieldNames.contains(field.name())) {
                        iter.remove();
                    }
                }
            } else {
                
                
                throw e;
            }
        }
        context.path().remove();
    }
    @Override
    public FieldMapper.Builder getMergeBuilder() {
        return new Builder(simpleName(), ignoreMalformedByDefault, indexCreatedVersion).metric(metricType).init(this);
    }
    @Override
    public SourceLoader.SyntheticFieldLoader syntheticFieldLoader() {
        if (ignoreMalformed) {
            throw new IllegalArgumentException(
                "field [" + name() + "] of type [" + typeName() + "] doesn't support synthetic source because it ignores malformed numbers"
            );
        }
        return new AggregateMetricSyntheticFieldLoader(name(), simpleName(), metrics);
    }
    public static class AggregateMetricSyntheticFieldLoader implements SourceLoader.SyntheticFieldLoader {