Improve portable skill validation workflows

[k-s-popova]

Summary

Improve the portability and reliability of skill authoring and verification workflows.

This change:

• Makes the distill skill platform-neutral and generates standard directory-based skills with SKILL.md.
• Updates verifying-skills to distinguish portable Agent Skills fields from host-specific extensions.
• Adds explicit unresolved P1/P2 counts to verification reports and enforces them in contribution validation.
• Preserves compatibility with existing zero-finding report wording.
• Corrects the Modern UI custom-control HTML filename example.
• Synchronizes affected discovery adapters, documentation, manifests, and verification reports.

Related Issue

Accepted proposal: None, internal maintenance

Affected Resources

Contribution workflow

• .github/PULL_REQUEST_TEMPLATE.md
• .github/scripts/validate-contribution.ps1
• CONTRIBUTING.md

Agent Tooling plugin

• Common/agent-tooling/skills/distill/SKILL.md
• Common/agent-tooling/skills/verifying-skills/SKILL.md
• Common/agent-tooling/skills/verifying-skills/references/checklist.md
• Common/agent-tooling/skills/verifying-skills/references/report-template.md
• Common/agent-tooling/README.md
• Common/agent-tooling/.claude-plugin/plugin.json
• Common/agent-tooling/.cursor-plugin/plugin.json
• Common/agent-tooling/.codex-plugin/plugin.json
• .github/skills/distill/SKILL.md
• .github/skills/verifying-skills/SKILL.md

DEV plugin

• DEV/skills/acumatica-modern-ui-control-builder/SKILL.md
• DEV/.claude-plugin/plugin.json
• DEV/.cursor-plugin/plugin.json
• DEV/.codex-plugin/plugin.json

Verification reports

• Verification/distill-review.md
• Verification/verifying-skills-review.md
• Verification/acumatica-modern-ui-control-builder-review.md

Verification

The repository contribution validator passed against origin/2026R1:

.github/scripts/validate-contribution.ps1 -BaseSha origin/2026R1 -HeadSha HEAD

Result: 5 skills, 5 GitHub Copilot adapters, and 2 plugins validated.

Local link validation also passed:

.github/scripts/check-links.ps1 -BaseSha origin/2026R1 -HeadSha HEAD

Result: links validated across 13 changed Markdown files.

Strict skill validation passed for:

• Common/agent-tooling/skills/distill
• Common/agent-tooling/skills/verifying-skills
• DEV/skills/acumatica-modern-ui-control-builder

Verification reports:

• Verification/distill-review.md
• Verification/verifying-skills-review.md
• Verification/acumatica-modern-ui-control-builder-review.md

All reports state:

• P1 findings open: 0
• P2 findings open: 0

No P3 findings were intentionally retained.

Additional checks confirmed:

• No files under Documentation/ changed.
• Affected manifest files contain valid JSON and synchronized versions.
• No obvious secrets, private URLs, customer data, or confidential information were detected.
• git diff --check passed.

Source and Licensing

No third-party code, assets, or other incorporated material is included. The verification guidance references publicly available skill-authoring documentation but does not reproduce third-party material.

OpenAI Codex assisted with auditing, editing, report preparation, and validation. I reviewed the resulting changes and take responsibility for their content.

Checklist

• This pull request targets 2026R1, the latest published release branch.
• The change is focused and links an accepted proposal when required.
• No file under Documentation/ is added, edited, moved, renamed, or deleted.
• Every added or changed skill was reviewed with verifying-skills.
• All P1 and P2 verification findings are resolved; applicable reports state P1 findings open: 0 and P2 findings open: 0.
• Applicable verification reports under Verification/ are added or updated.
• Affected AI tool manifests contain valid JSON and the same version.
• The plugin version was incremented when required.
• Relevant README and marketplace entries are current.
• Local links resolve and referenced files exist.
• The contribution contains no secrets, private URLs, customer data, or confidential information.
• I have the right to submit all included material under GNU GPL version 3.
• Every commit includes a DCO Signed-off-by line.