Fix: cluster settings can be flat.

[dblock]

Description

Cluster settings don't always return nested objects, they can be flat key/value pairs.

Here's the default output with include_defaults on the test cluster, note processors.

    "logger": {
      "level": "INFO"
    },
    "processors": "10",
    "ingest": {
      "geoip": {
        "cache_size": "1000"
      },

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[github-actions]

Changes Analysis

Commit SHA: 5a7af53
Comparing To SHA: 3f806a1

API Changes

Summary

└─┬Paths
  └─┬/_cluster/settings
    └─┬GET
      └─┬Responses
        └─┬200
          └─┬application/json
            └─┬Schema
              ├─┬transient
              │ └──[🔀] additionalProperties (25466:39)❌ 
              ├─┬defaults
              │ └──[🔀] additionalProperties (25469:39)❌ 
              └─┬persistent
                └──[🔀] additionalProperties (25463:39)❌ 

Document Element	Total Changes	Breaking Changes
paths	3	3

• ❌ BREAKING Changes: 3 out of 3
• Modifications: 3
• Breaking Modifications: 3

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/10637361428/artifacts/1875965144

API Coverage

	Before	After	Δ
Covered (%)	533 (52.2 %)	533 (52.2 %)	0 (0 %)
Uncovered (%)	488 (47.8 %)	488 (47.8 %)	0 (0 %)
Unknown	26	26	0

[github-actions]

Spec Test Coverage Analysis

Total	Tested
559	249 (44.54 %)