Add mobile best practices skill documentation

[tungnk123]

Pull Request Checklist

• I have read and followed the CONTRIBUTING.md guidelines.
• 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.

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Description

Adding a mobile-best-practices skill — a searchable database of 2,461
curated guidelines for Android, iOS, Flutter, and React Native.

Covers architecture patterns, security (OWASP Mobile Top 10), performance
rules, UI patterns, anti-patterns, and copy-paste code snippets. Uses BM25
ranking with fuzzy search across 16 CSV databases.

Useful for: code reviews, architecture decisions, security audits,
performance optimization, and library selection across all major mobile
platforms.

Source: https://github.com/tungnk123/mobile-best-practices

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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

The skill includes:

• 792 platform-specific guidelines (Android, iOS, Flutter, React Native)
• 437 security practices mapped to OWASP Mobile Top 10
• 228 performance rules
• 243 anti-patterns
• 81 copy-paste code snippets
• 78 Gradle dependency declarations

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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.

[aaronpowell]

It looks like you've incorrectly branched from the main branch not staged, and as a result all the materialised plugins are included in this PR.

You can attempt to fix this with a rebase:

git fetch origin staged
git rebase --onto origin/staged origin/main <branch name>
git push --force-with-lease

If that does not resolve it, you can run npm run plugin:clean which will delete the materialised plugins and you can commit that change.

[tungnk123]

Hi @aaronpowell, thanks for the guidance! I've applied the rebase as suggested:

git fetch upstream staged
git rebase --onto upstream/staged upstream/main main
git push origin main --force-with-lease

The PR now only includes skills/mobile-best-practices/SKILL.md — all the materialised plugins have been removed from the diff. Please let me know if anything else needs to be adjusted.