Added specs and tests for /_plugins/_transform.

[dblock]

Description

Added/corrected responses for /_plugins/_transform.

Issues Resolved

Part of #663.

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[github-actions]

Changes Analysis

Commit SHA: 1bc79c2
Comparing To SHA: 4f28c29

API Changes

Summary

├─┬Paths
│ ├─┬/_plugins/_transform/{id}
│ │ ├─┬GET
│ │ │ └─┬Responses
│ │ │   └─┬200
│ │ │     └─┬application/json
│ │ │       └─┬Schema
│ │ │         └──[🔀] $ref (59376:13)❌ 
│ │ ├─┬PUT
│ │ │ ├─┬Responses
│ │ │ │ ├──[➕] codes (31933:7)
│ │ │ │ └─┬200
│ │ │ │   └─┬application/json
│ │ │ │     └─┬Schema
│ │ │ │       └──[🔀] $ref (59376:13)❌ 
│ │ │ └─┬Requestbody
│ │ │   └─┬application/json
│ │ │     └─┬Schema
│ │ │       └──[🔀] $ref (59369:13)❌ 
│ │ └─┬DELETE
│ │   └─┬Responses
│ │     └─┬200
│ │       └──[➕] content (31905:11)
│ └─┬/_plugins/_transform/_preview
│   └─┬POST
│     └─┬Requestbody
│       └──application/json
└─┬Components
  ├──[➕] responses (31933:7)
  ├──[➖] schemas (59228:7)❌ 
  ├──[➖] schemas (59217:7)❌ 
  ├──[➖] schemas (59314:7)❌ 
  ├──[➕] schemas (59180:7)
  ├──[➕] schemas (59369:7)
  ├──[➕] schemas (59219:7)
  ├──[➕] schemas (59376:7)
  ├──[➕] schemas (59214:7)
  ├─┬transforms._common___TransformsResponse
  │ └─┬transforms
  │   └─┬Schema
  │     └──[🔀] $ref (59376:13)❌ 
  ├─┬transforms._common___Explain
  │ ├─┬metadata_id
  │ │ └──[🔀] type (59235:13)❌ 
  │ └─┬transform_metadata
  │   └──[🔀] $ref (59238:11)❌ 
  └─┬transforms._common___Transform
    ├─┬aggregations
    │ ├──[➕] additionalProperties (59352:13)❌ 
    │ ├──[➖] items (59312:13)❌ 
    │ └──[🔀] type (59350:17)❌ 
    ├─┬enabled_at
    │ └──[🔀] type (59329:13)❌ 
    ├─┬metadata_id
    │ └──[🔀] type (59321:13)❌ 
    └─┬updated_at
      └──[🔀] type (59324:17)❌ 

Document Element	Total Changes	Breaking Changes
paths	5	3
components	18	12

• ❌ BREAKING Changes: 15 out of 23
• Modifications: 10
• Removals: 4
• Additions: 9
• Breaking Removals: 4
• Breaking Modifications: 10
• Breaking Additions: 1

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/12263435686/artifacts/2301936562

API Coverage

	Before	After	Δ
Covered (%)	606 (59.35 %)	606 (59.35 %)	0 (0 %)
Uncovered (%)	415 (40.65 %)	415 (40.65 %)	0 (0 %)
Unknown	43	43	0

[github-actions]

Spec Test Coverage Analysis

Total	Tested
536	467 (87.13 %)