### Description

Dynamic mappings can greatly help the getting started experience but they currently don't apply to all types, one example is `dense_vector`.

It's been suggested to automatically map float arrays as dense vectors when there are more than 100 values, or a heuristic along these lines.
server/src/main/java/org/elasticsearch/index/mapper/DocumentParser.java
if (parsesArrayValue(mapper)) {
                parseObjectOrField(context, mapper);
            } else {
                parseNonDynamicArray(context, lastFieldName, lastFieldName);
            }
        } else {
            if (context.dynamic() == ObjectMapper.Dynamic.STRICT) {
                throw new StrictDynamicMappingException(context.parser().getTokenLocation(), context.parent().fullPath(), lastFieldName);
            } else if (context.dynamic() == ObjectMapper.Dynamic.FALSE) {
                context.parser().skipChildren();
            } else {
                Mapper objectMapperFromTemplate = DynamicFieldsBuilder.createObjectMapperFromTemplate(context, lastFieldName);
                if (objectMapperFromTemplate == null) {
                    parseNonDynamicArray(context, lastFieldName, lastFieldName);
                } else {
                    if (parsesArrayValue(objectMapperFromTemplate)) {
                        context.addDynamicMapper(objectMapperFromTemplate);
                        context.path().add(lastFieldName);
                        parseObjectOrField(context, objectMapperFromTemplate);
                        context.path().remove();
                    } else {
                        parseNonDynamicArray(context, lastFieldName, lastFieldName);
                    }
                }
            }
        }
    }
    private static boolean parsesArrayValue(Mapper mapper) {