Added ML Model APIs

[nathaliellenaa]

Description

Added GET /_plugins/_ml/models/{id}, POST /_plugins/_ml/models/_search, and PUT /_plugins/_ml/models/{id}.

Issues Resolved

Part of opensearch-project/opensearch-py#867.

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[github-actions]

Changes Analysis

Commit SHA: 1420d16
Comparing To SHA: dd7fd9a

API Changes

Summary

├─┬Paths
│ ├─┬/_plugins/_ml/models/{model_id}
│ │ ├──[➕] get (4802:7)
│ │ └──[➕] put (4816:7)
│ └─┬/_plugins/_ml/models/_search
│   └──[➕] post (4772:7)
└─┬Components
  ├──[➕] requestBodies (27240:7)
  ├──[➕] responses (30335:7)
  ├──[➕] responses (30282:7)
  ├──[➕] parameters (22919:7)
  ├──[➕] parameters (22901:7)
  ├──[➕] schemas (54080:7)
  ├──[➕] schemas (53726:7)
  ├──[➕] schemas (53844:7)
  ├──[➕] schemas (53686:7)
  └──[➕] schemas (53655:7)

Document Element	Total Changes	Breaking Changes
paths	3	0
components	10	0

• Total Changes: 13
• Additions: 13

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/12323574180/artifacts/2319624073

API Coverage

	Before	After	Δ
Covered (%)	606 (59.35 %)	609 (59.65 %)	3 (0.3 %)
Uncovered (%)	415 (40.65 %)	412 (40.35 %)	-3 (-0.3 %)
Unknown	43	43	0

[github-actions]

Spec Test Coverage Analysis

Total	Tested
539	490 (90.91 %)

[dblock]

Looking good. I have some smallish nits. Iterate to green (validation is failing, etc.)

[dblock]

Btw, there's a whole bunch of others missing per #168. They don't all need to be done at the same time.

[nathaliellenaa]

Yes, I'm planning to create some small PRs based on the APIs category (model, model groups, connector, agents, etc.) I will also add more missing Model APIs to this PR.