Add ML Stats APIs

[nathaliellenaa]

Description

Added missing ML Stats APIs.

Issues Resolved

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

ML Stats APIs to add

• GET /_plugins/_ml/stats/
• GET /_plugins/_ml/stats/{stat}
• GET /_plugins/_ml/{nodeId}/stats/
• GET /_plugins/_ml/{nodeId}/stats/{stat}

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[github-actions]

Changes Analysis

Commit SHA: b380fe3
Comparing To SHA: 806b25f

API Changes

Summary

├─┬Paths
│ ├──[➕] path (4706:3)
│ ├──[➕] path (4690:3)
│ ├──[➕] path (5649:3)
│ └──[➕] path (5664:3)
└─┬Components
  ├──[➕] responses (31886:7)
  ├──[➕] parameters (23828:7)
  ├──[➕] parameters (23822:7)
  ├──[➕] schemas (56181:7)
  ├──[➕] schemas (55733:7)
  ├──[➕] schemas (56185:7)
  ├──[➕] schemas (55645:7)
  ├──[➕] schemas (55554:7)
  ├──[➕] schemas (56291:7)
  ├──[➕] schemas (56132:7)
  ├──[➕] schemas (56902:7)
  ├──[➕] schemas (55567:7)
  ├──[➕] schemas (56940:7)
  ├──[➕] schemas (56460:7)
  └─┬ml._common___ModelProfile
    ├──[➕] properties (56117:9)
    ├──[➕] properties (56123:9)
    ├──[➕] properties (56119:9)
    ├──[➕] properties (56125:9)
    └──[➕] properties (56121:9)

Document Element	Total Changes	Breaking Changes
paths	4	0
components	19	0

• Total Changes: 23
• Additions: 23

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/12778530314/artifacts/2431645031

API Coverage

	Before	After	Δ
Covered (%)	652 (63.86 %)	655 (64.15 %)	3 (0.29 %)
Uncovered (%)	369 (36.14 %)	366 (35.85 %)	-3 (-0.29 %)
Unknown	43	44	1

[github-actions]

Spec Test Coverage Analysis

Total	Tested
586	585 (99.83 %)