### 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/test/java/org/elasticsearch/xpack/aggregatemetric/mapper/AggregateDoubleMetricFieldMapperTests.java
containsString("Aggregate metric field [field] must contain all metrics [min, max, value_count]")
        );
    }
    @Override
    protected boolean supportsIgnoreMalformed() {
        return true;
    }
    @Override
    protected List<ExampleMalformedValue> exampleMalformedValues() {
        return List.of(
            
            exampleMalformedValue(b -> b.startObject().endObject()).errorMatches(
                "Aggregate metric field [field] must contain all metrics [min, max, value_count]"
            ),
            
            exampleMalformedValue(
                b -> b.startObject().field("min", -10.1).field("max", 50.0).field("value_count", 14).field("sum", 55).endObject()
            ).errorMatches("Aggregate metric [sum] does not exist in the mapping of field [field]"),
            
            exampleMalformedValue(b -> b.startObject().field("min", -10.1).field("max", 50.0).endObject()).errorMatches(
                "Aggregate metric field [field] must contain all metrics [min, max, value_count]"
            ),
            
            exampleMalformedValue(b -> b.startObject().field("min", "10.0").field("max", 50.0).field("value_count", 14).endObject())
                .errorMatches("Failed to parse object: expecting token of type [VALUE_NUMBER] but found [VALUE_STRING]"),
            
            exampleMalformedValue(b -> b.startObject().field("min", 10.0).field("max", 50.0).field("value_count", -14).endObject())
                .errorMatches("Aggregate metric [value_count] of field [field] cannot be a negative number"),
            
            exampleMalformedValue(b -> b.startObject().field("min", 10.0).field("max", 50.0).field("value_count", 77.33).endObject())