Add UIZZE anti-ui-slop plugin

[samuelbushi]

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, workflow, or canvas extension 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, workflow, or canvas extension with GitHub Copilot.
• I have run npm start and verified that README.md is up to date.
• I am targeting the main branch for this pull request.

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Description

Adds uizze, a default-marketplace plugin that packages the existing anti-ui-slop skill merged in #2351. Users can install the workflow with:

copilot plugin install uizze@awesome-copilot

The plugin turns real interface evidence into a product-specific design contract, then enforces the skill's finish gate before the UI is considered complete. It requires no account, credential, token, external server, or MCP configuration. The public UIZZE catalogue is the skill's reference source; the workflow remains usable with user-provided references or repository evidence when browsing is unavailable.

This is distinct from #2389: that pull request improves the link placement inside the existing skill, while this pull request adds the installable Copilot plugin manifest, plugin documentation, generated marketplace entry, and generated plugin index entry. It does not modify the skill.

Affiliation disclosure: I maintain UIZZE. The bundled skill is free, MIT licensed, and useful without any paid service. The plugin contains no pricing, signup prompt, telemetry, token, or paid MCP integration.

Validation completed:

• npm run plugin:validate — all 71 plugins, 19 extensions, and 33 external entries passed
• npm run skill:validate — anti-ui-slop passed
• npm start — marketplace and documentation generated successfully
• npx --yes @microsoft/vally-cli lint skills/anti-ui-slop --verbose — 2/2 checks passed
• publish materialization copied the canonical skill into plugins/uizze/skills/anti-ui-slop/ byte-for-byte
• Vally passed again against the materialized plugin skill
• bash eng/fix-line-endings.sh
• git diff --check
• https://uizze.com returned HTTP 200

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Type of Contribution

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

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Additional Notes

The plugin deliberately omits the optional paid MCP server. That keeps the default-marketplace install self-contained, credential-free, and aligned with the repository's guidance for vendor-backed contributions.

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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.

[github-actions]

🔒 PR Risk Scan Results

Scanned 4 changed file(s).

Severity	Count
🔴 High	0
🟠 Medium	0
ℹ️ Info	0

✅ No matching risk patterns were detected in changed files.

This is an automated soft-gate report. Findings indicate review targets and do not block merge by themselves.

[github-actions]

🔴 Contributor Reputation Check: HIGH risk

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Profile	HIGH
Credential audit	NONE

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