Add SkillCheck validation badges to passing skills

[olgasafonova]

Summary

Several skills in this repository pass SkillCheck validation checks. SkillCheck validates Claude Code skills against the agentskills specification, MCP best practices, and WCAG accessibility standards.

Skills that pass validation

Skill	Status	Available Badges
semgrep-rule-creator	✅ PASS	wcag-aa, wcag-aaa
modern-python	✅ PASS	enterprise, antislop-90
property-based-testing	✅ PASS	passed, wcag-aa

Proposal

Would you be interested in adding SkillCheck badges to the READMEs for these skills? The badges help users identify quality-validated skills.

Example badge:

[![SkillCheck Passed](https://img.shields.io/badge/SkillCheck-Passed-brightgreen)](https://getskillcheck.com)

I'm happy to submit a PR with the badges if you're interested.

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Generated by reviewing skills from the Claude Skills: 36 Examples article.

[olgasafonova]

Update: Additional passing skills found

After more comprehensive testing, here are additional skills that pass validation:

Skill	Status	Available Badges
insecure-defaults	✅ PASS	-
entry-point-analyzer	✅ PASS	-
differential-review	✅ Needs Attention	-
fix-review	✅ Needs Attention	-
audit-context-building	✅ Needs Attention	-

Full list of skills that pass (no critical issues):

1. semgrep-rule-creator
2. modern-python
3. property-based-testing
4. insecure-defaults
5. entry-point-analyzer
6. differential-review
7. fix-review
8. audit-context-building

Happy to create a PR adding badges to any or all of these!