Add editorial comments to async search descriptions

[Naarcha-AWS]

Adds comments from PR opensearch-project#781

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[github-actions]

Changes Analysis

Commit SHA: 4a9a48f
Comparing To SHA: 799d046

API Changes

Summary

└─┬Paths
  ├─┬/_plugins/_asynchronous_search/stats
  │ └─┬GET
  │   └──[🔀] description (3707:20)
  ├─┬/_plugins/_asynchronous_search
  │ └─┬POST
  │   ├─┬Parameters
  │   │ └──[🔀] description (15990:20)
  │   ├─┬Parameters
  │   │ └──[🔀] description (16005:20)
  │   └─┬Parameters
  │     └──[🔀] description (15999:20)
  ├─┬/_opendistro/_asynchronous_search
  │ └─┬POST
  │   ├─┬Parameters
  │   │ └──[🔀] description (16005:20)
  │   ├─┬Parameters
  │   │ └──[🔀] description (15990:20)
  │   └─┬Parameters
  │     └──[🔀] description (15999:20)
  └─┬/_opendistro/_asynchronous_search/stats
    └─┬GET
      └──[🔀] description (13510:20)

Document Element	Total Changes	Breaking Changes
paths	8	0

• Total Changes: 8
• Modifications: 8

Report

The full API changes report is available at: https://github.com/Naarcha-AWS/opensearch-api-specification/actions/runs/12952510408/artifacts/2481523922

API Coverage

	Before	After	Δ
Covered (%)	662 (64.84 %)	662 (64.84 %)	0 (0 %)
Uncovered (%)	359 (35.16 %)	359 (35.16 %)	0 (0 %)
Unknown	45	45	0

[github-actions]

Spec Test Coverage Analysis

Total	Tested
594	593 (99.83 %)