### 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/DynamicFieldsBuilder.java
}
    private static Mapper.Builder findTemplateBuilderForObject(DocumentParserContext context, String name) {
        DynamicTemplate.XContentFieldType matchType = DynamicTemplate.XContentFieldType.OBJECT;
        DynamicTemplate dynamicTemplate = context.findDynamicTemplate(name, matchType);
        if (dynamicTemplate == null) {
            return null;
        }
        String dynamicType = matchType.defaultMappingType();
        String mappingType = dynamicTemplate.mappingType(dynamicType);
        Map<String, Object> mapping = dynamicTemplate.mappingForName(name, dynamicType);
        return parseDynamicTemplateMapping(name, mappingType, mapping, null, context);
    }
    private static Mapper.Builder parseDynamicTemplateMapping(
        String name,
        String mappingType,
        Map<String, Object> mapping,
        DateFormatter dateFormatter,
        DocumentParserContext context
    ) {
        MappingParserContext parserContext = context.dynamicTemplateParserContext(dateFormatter);
        Mapper.TypeParser typeParser = parserContext.typeParser(mappingType);
        if (typeParser == null) {
            throw new MapperParsingException("failed to find type parsed [" + mappingType + "] for [" + name + "]");
        }
        return typeParser.parse(name, mapping, parserContext);
    }
    /**
     * Defines how leaf fields of type string, long, double, boolean and date are dynamically mapped
     */
    private interface Strategy {