feat(MLX): add Semantic search preview

[paulgerold]

Add the semantic search preview :

https://platformdev.cloud.coveo.com/docs?urls.primaryName=Machine%20Learning%20Configuration#/Semantic%20Search%20Configuration/rest_organizations_paramId_machinelearning_configuration_ses_preview_post

Acceptance Criteria

• My changes are publicly available, documented, and deployed in production. (i.e. on Swagger)
• JSDoc annotates each property added in the exported interfaces
• The proposed changes are covered by unit tests
• Commits containing breaking changes a properly identified as such
• README.md is adjusted to reflect the proposed changes (if relevant)
• My merge commit message will be conventional (See Conventional Commit)

[fbeaudoincoveo]

I mostly have docs-related comments / questions. If you choose to apply my comments, you should also update the Swagger docs accordingly.

[paulgerold]

@fbeaudoincoveo Hello I updated some text to reflect the text of the API already reviewed and approved :
https://github.com/coveo/ml-config-service/blob/master/coveo-cloud-ml-config-api/src/main/java/com/coveo/cloud/mlconfig/model/semanticsearch/SemanticSearchPreviewRequest.java

https://github.com/coveo/ml-config-service/blob/master/coveo-cloud-ml-config-api/src/main/java/com/coveo/cloud/mlconfig/model/semanticsearch/SemanticSearchPreviewResponse.java

[github-actions]

🎉 This PR is included in version 49.2.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀