Draft Watsonx inference API

[lcawl]

Relates to #3821, elastic/elasticsearch#115088

This PR is an attempt to handle the Watsonx inference use case, with content derived from https://www.elastic.co/guide/en/elasticsearch/reference/current/infer-service-watsonx-ai.html

The following linting error occurs:

  9040:5    warning  no-identical-paths             The path already exists which differs only by path parameter name(s): `/_inference/{task_type}/{inference_id}` and `/_inference/{task_type}/{watsonx_inference_id}`.

This is essentially because there are multiple paths that are interchangeable (since neither the task type nor the inference ID in the path are unique to each of these variations). We are currently treating that type of lint message as a warning, however, so if that's the best method to represent these endpoints the linting message is acceptable IMO.

[github-actions]

Following you can find the validation results for the APIs you have changed.

API	Status	Request	Response
inference.put_watsonx	⚪	Missing test	Missing test

You can validate these APIs yourself by using the make validate target.

[flobernd]

LGTM from my side. Thank you 🙂 Maybe Laura wants to double check.

[github-actions]

Following you can find the validation results for the APIs you have changed.

API	Status	Request	Response
inference.delete	⚪	Missing test	Missing test
inference.get	🟢	1/1	1/1
inference.inference	⚪	Missing test	Missing test
inference.put_watsonx	⚪	Missing test	Missing test
inference.put	⚪	Missing test	Missing test
inference.stream_inference	⚪	Missing test	Missing test
inference.unified_inference	⚪	Missing test	Missing test
inference.update	⚪	Missing test	Missing test

You can validate these APIs yourself by using the make validate target.

[l-trotta]

LGTM!

[github-actions]

The backport to 8.x failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-8.x 8.x
# Navigate to the new working tree
cd .worktrees/backport-8.x
# Create a new branch
git switch --create backport-3866-to-8.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 16c8bd383b6caa644ab64a57e989bb1d75b8b458
# Push it to GitHub
git push --set-upstream origin backport-3866-to-8.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-8.x

Then, create a pull request where the base branch is 8.x and the compare/head branch is backport-3866-to-8.x.

[github-actions]

The backport to 8.18 failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-8.18 8.18
# Navigate to the new working tree
cd .worktrees/backport-8.18
# Create a new branch
git switch --create backport-3866-to-8.18
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 16c8bd383b6caa644ab64a57e989bb1d75b8b458
# Push it to GitHub
git push --set-upstream origin backport-3866-to-8.18
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-8.18

Then, create a pull request where the base branch is 8.18 and the compare/head branch is backport-3866-to-8.18.

[lcawl]

💚 All backports created successfully

Status	Branch	Result
✅	8.x

Questions ?

Please refer to the Backport tool documentation

[github-actions]

The backport to 8.17 failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-8.17 8.17
# Navigate to the new working tree
cd .worktrees/backport-8.17
# Create a new branch
git switch --create backport-3866-to-8.17
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 16c8bd383b6caa644ab64a57e989bb1d75b8b458
# Push it to GitHub
git push --set-upstream origin backport-3866-to-8.17
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-8.17

Then, create a pull request where the base branch is 8.17 and the compare/head branch is backport-3866-to-8.17.

[lcawl]

💚 All backports created successfully

Status	Branch	Result
✅	8.18

Questions ?

Please refer to the Backport tool documentation