### 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
@Deprecated
    public final DocumentParserContext switchParser(XContentParser parser) {
        return new Wrapper(this.parent, this) {
            @Override
            public XContentParser parser() {
                return parser;
            }
        };
    }
    /**
     * The collection of dimensions for this document.
     */
    public DocumentDimensions getDimensions() {
        return dimensions;
    }
    public abstract ContentPath path();
    /**
     * Creates a context to build dynamic mappers
     */
    public final MapperBuilderContext createDynamicMapperBuilderContext() {
        String p = path().pathAsText("");
        if (p.endsWith(".")) {
            p = p.substring(0, p.length() - 1);
        }
        return new MapperBuilderContext(p, mappingLookup().isSourceSynthetic());
    }
    public abstract XContentParser parser();
    public abstract LuceneDocument rootDoc();
    public abstract LuceneDocument doc();
    protected abstract void addDoc(LuceneDocument doc);