### 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_
test/framework/src/main/java/org/elasticsearch/index/mapper/MapperTestCase.java
* @param param  the parameter name, expected to appear in the error message
         * @param init   the initial mapping
         * @param update the updated mapping
         */
        public void registerConflictCheck(String param, XContentBuilder init, XContentBuilder update) {
            conflictChecks.put(param, new ConflictCheck(init, update));
        }
    }
    protected abstract void registerParameters(ParameterChecker checker) throws IOException;
    public void testUpdates() throws IOException {
        ParameterChecker checker = new ParameterChecker();
        registerParameters(checker);
        if (supportsIgnoreMalformed()) {
            checker.registerUpdateCheck(b -> b.field("ignore_malformed", true), m -> assertTrue(m.ignoreMalformed()));
        } else {
            MapperService mapperService = createMapperService(fieldMapping(this::minimalMapping));
            Exception e = expectThrows(
                MapperParsingException.class,
                "No conflict when setting parameter [ignore_malformed]",
                () -> merge(mapperService, fieldMapping(b -> {
                    minimalMapping(b);
                    b.field("ignore_malformed", true);
                }))
            );
            assertThat(e.getMessage(), containsString("unknown parameter [ignore_malformed] on mapper [field]"));
        }
        for (UpdateCheck updateCheck : checker.updateChecks) {
            MapperService mapperService = createMapperService(updateCheck.init);
            merge(mapperService, updateCheck.update);
            FieldMapper mapper = (FieldMapper) mapperService.documentMapper().mappers().getMapper("field");