Provide OpenAPI/Swagger specification out of the box

[elasticmachine]

Original comment by @lcawl:

This issue is related to #25152

I have been formatting the X-Pack API reference information such that it uses the same section headers as the Cloud Enterprise documentation, which in turn was generated from Swagger.

I would like to pursue whether we can go one step further and start generating the X-Pack API information from Swagger too. This would help avoid situations where the documentation gets out of synch with the API code.

If it is not possible to include our current level of code snippet testing in the Swagger-generated files, we will need to investigate options for appending that information.

[elasticmachine]

Original comment by @lcawl:

Some information about how the Cloud team implemented this is here: LINK REDACTED

[elasticmachine]

Pinging @elastic/es-core-infra

[javanna]

Should this be considered a duplicate of #25152 ?

[jrodewig]

[docs issue triage]

Closing as there are no current plans to provide OpenAPI/Swagger spec. More discussion at #25152.

Meanwhile, we've created the Elastic API Reference template as part of elastic/docs#937.

We're working to migrate Elasticsearch API Reference documentation to this template format as part of #45195.