Allow key-based yaml anchoring

[RensR]

This pull request enhances the Chainlink Deployments Framework's YAML parsing to provide robust support for YAML anchors and merge keys (<<), ensuring that complex YAML features are correctly handled when processing pipeline input files. The changes also improve error handling and extend test coverage for these YAML features.

eg

a: &a
  x: from_a
  only_a: 1
b: &b
  x: from_b
  only_b: 2
m:
  <<: [*a, *b]

[changeset-bot]

🦋 Changeset detected

Latest commit: 438c3aa

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
chainlink-deployments-framework	Minor

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[Copilot]

Pull request overview

This PR improves YAML handling in the CLD pipeline input layer to correctly support YAML anchors/aliases and merge keys (<<), allowing more complex YAML inputs to be decoded into JSON-safe structures while preserving numeric fidelity (e.g., json.Number).

Changes:

• Added key stringification helper (anyToJSONMapKey) and enhanced YAML node decoding to support alias keys and merge keys (<<) with error reporting.
• Updated YAML parsing and config resolution paths to propagate decode errors from YamlNodeToAny.
• Expanded unit tests to cover alias keys, merge keys, and invalid merge values; added a changeset entry.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
engine/cld/pipeline/input/yaml.go	Implements YAML node-to-any decoding with merge key support and improved map-key handling.
engine/cld/pipeline/input/yaml_test.go	Adds tests for alias map keys, merge keys, invalid merge values, and JSON-safe key conversion.
engine/cld/pipeline/input/resolve.go	Propagates YAML decode errors when resolving changeset configs.
.changeset/loud-trams-jog.md	Declares a minor release entry for the YAML anchor/merge support feature.

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[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

[graham-chainlink]

unfortunately this was suppose to be exported , but currently single usage in Chainlink repo so we have to maintain this signature for now.

[cl-sonarqube-production]

Quality Gate failed

Failed conditions
72.0% Coverage on New Code (required ≥ 80%)

See analysis details on SonarQube