feat: introduce skillsSupported feature flag #1975

[astsiapanay]

Adds a skillsSupported feature flag so DIAL clients can detect whether a deployment/model accepts custom skills via messages[*].custom_content.skills[*] in chat completion requests.

Applicable issues

• fixes Introduce feature flag skillsSupported #1975

Description of changes

• Added skillsSupported to Features (config module), following the same @JsonAlias/merge pattern as the other *Supported flags.
• Added skillsSupported to FeaturesData (server module), defaulting to false, mapped from Features.getSkillsSupported() in createFeatures().
• Updated hard-coded expected features JSON blocks in ToolSetApiTest, ListingTest, ApplicationDeploymentApiTest, and CustomApplicationApiTest to include the new flag.
• Regenerated docs/open_api_core.yaml to add skills_supported: boolean to the Features/FeaturesData schemas.

Checklist

• Title of the pull request follows Conventional Commits specification

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[ai-dial-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

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