Add support for application/smile

[dblock]

Description

Add support for application/smile.

Thanks to @ngyewch for the recent work on the smile-js library to get this over the line!

Issues Resolved

Closes #372.

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[github-actions]

Changes Analysis

Commit SHA: ab88a52
Comparing To SHA: ba3d715

API Changes

Summary

└─┬Paths
  ├─┬/_cat/indices
  │ └─┬GET
  │   └─┬Responses
  │     └─┬200
  │       └──[➕] content (23228:11)
  ├─┬/_cat/health
  │ └─┬GET
  │   └─┬Responses
  │     └─┬200
  │       └──[➕] content (23197:11)
  └─┬/_cat/indices/{index}
    └─┬GET
      └─┬Responses
        └─┬200
          └──[➕] content (23228:11)

Document Element	Total Changes	Breaking Changes
paths	3	0

• Total Changes: 3
• Additions: 3

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/9865817894/artifacts/1684368883

API Coverage

	Before	After	Δ
Covered (%)	483 (47.31 %)	483 (47.31 %)	0 (0 %)
Uncovered (%)	538 (52.69 %)	538 (52.69 %)	0 (0 %)
Unknown	24	24	0

[Xtansia]

Are we not actually validating content_type against the response content-type header?

[dblock]

Looks like it, #392.

[Xtansia]

As above regarding validating content_type as test is supposed to be for smile but format is set to cbor

[dblock]

Updated to be format: smile.