### 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/DocumentParserContext.java
public ObjectMapper.Dynamic dynamic() {
        return dynamic;
    }
    /**
     * Add a new mapper dynamically created while parsing.
     */
    public final void addDynamicMapper(Mapper mapper) {
        
        if (mapper instanceof ObjectMapper) {
            MappingLookup.checkObjectDepthLimit(indexSettings().getMappingDepthLimit(), mapper.name());
        }
        
        
        
        if (mappingLookup.getMapper(mapper.name()) == null
            && mappingLookup.objectMappers().containsKey(mapper.name()) == false
            && newFieldsSeen.add(mapper.name())) {
            mappingLookup.checkFieldLimit(indexSettings().getMappingTotalFieldsLimit(), newFieldsSeen.size());
        }
        if (mapper instanceof ObjectMapper objectMapper) {
            dynamicObjectMappers.put(objectMapper.name(), objectMapper);
            
            
            for (Mapper submapper : objectMapper.mappers.values()) {
                
                
                
                addDynamicMapper(submapper);
            }
        }