[ML] Block updates to trained model deployments managed by the Elasticsearch Inference service

[davidkyle]

Elasticsearch Version

main

Installed Plugins

No response

Java Version

bundled

OS Version

any

Problem Description

#129325 blocks the trained model stop deployment API from stopping a deployment owned by an Inference endpoint. Similarly update operations via the trained models update API should be disabled for POST _ml/trained_models/my-deployment/deployment/_update. These deployments should be managed via the Inference API.

Steps to Reproduce

POST _ml/trained_models/.elser-2-elasticsearch/deployment/_update

Logs (if relevant)

No response

[elasticsearchmachine]

Pinging @elastic/ml-core (Team:ML)

[prwhelan]

Do we then need to let inference endpoints update adaptive allocation settings? Right now I think it only allows num_allocations: https://github.com/elastic/elasticsearch/blob/main/x-pack/plugin/inference/src/main/java/org/elasticsearch/xpack/inference/action/TransportUpdateInferenceModelAction.java#L266