Fix gh skill command to gh skills and update README

[aaronpowell]

Correct the command from gh skill install to gh skills install in the codebase and update the README to reflect this change. This ensures accurate usage instructions for users.

Pull Request Checklist

• I have read and followed the CONTRIBUTING.md guidelines.
• I have read and followed the Guidance for submissions involving paid services.
• My contribution adds a new instruction, prompt, agent, skill, or workflow file in the correct directory.
• The file follows the required naming convention.
• The content is clearly structured and follows the example format.
• I have tested my instructions, prompt, agent, skill, or workflow with GitHub Copilot.
• I have run npm start and verified that README.md is up to date.
• I am targeting the staged branch for this pull request.

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Description

Correct the command from gh skill install to gh skills install in the codebase and update the README to reflect this change. This ensures accurate usage instructions for users.

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Type of Contribution

• New instruction file.
• New prompt file.
• New agent file.
• New plugin.
• New skill file.
• New agentic workflow.
• Update to existing instruction, prompt, agent, plugin, skill, or workflow.
• Other (please specify):

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Additional Notes

No additional notes.

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By submitting this pull request, I confirm that my contribution abides by the Code of Conduct and will be licensed under the MIT License.

[Copilot]

Pull request overview

This PR updates the repo’s skill installation command from gh skill install to gh skills install across the website UI and generated documentation so users see the correct GitHub CLI usage.

Changes:

• Update website install-command copy actions (skills list + modal) to use gh skills install.
• Update skills documentation templates and generated docs/README.skills.md to reflect the corrected command.
• Apply minor formatting/quoting consistency improvements in touched website/eng scripts.

Show a summary per file

File	Description
website/src/scripts/utils.ts	Updates REPO_IDENTIFIER doc comment to reference gh skills install.
website/src/scripts/pages/skills.ts	Updates copied install command to gh skills install; minor formatting/quote consistency.
website/src/scripts/modal.ts	Updates modal install command to gh skills install; formatting-only refactors.
eng/update-readme.mjs	Updates skills README generation to include gh skills install (and adds per-skill command in the table).
eng/constants.mjs	Updates the skills usage template to show gh skills install.
docs/README.skills.md	Updates rendered skills README usage line and table entries to use gh skills install.

Copilot's findings

• Files reviewed: 5/6 changed files
• Comments generated: 2