### Elasticsearch Version

main

### Installed Plugins

_No response_

### Java Version

_bundled_

### OS Version

Darwin

### Problem Description

Sorting fails sometimes with the error

```
No TopN sorting encoder for type UNSUPPORTED
```


### Steps to Reproduce

Playing with ES|QL I tried to run the following query

`from logstash-* | sort extension.keyword`

This returns the error

```
No TopN sorting encoder for type UNSUPPORTED
```

If I run the query:

`from logstash-*  | keep extension.keyword | sort extension.keyword`

the data return successfully.

### Logs (if relevant)

_No response_
x-pack/plugin/esql/compute/src/main/java/org/elasticsearch/compute/operator/topn/TopNEncoder.java
/**
     * An encoder that encodes values such that sorting the bytes sorts the values.
     */
    DefaultSortableTopNEncoder DEFAULT_SORTABLE = new DefaultSortableTopNEncoder();
    /**
     * An encoder that encodes values as compactly as possible without making the
     * encoded bytes sortable.
     */
    DefaultUnsortableTopNEncoder DEFAULT_UNSORTABLE = new DefaultUnsortableTopNEncoder();
    /**
     * An encoder for IP addresses.
     */
    FixedLengthTopNEncoder IP = new FixedLengthTopNEncoder(InetAddressPoint.BYTES);