Create guide and evals for the security use case

[chrome-devrel-infra]

Preventative security guidelines for web developers (XSS, CSP, Cookies, Cross-Origin Isolation). Use this skill to guide the process of auditing, testing, and deploying security policies safely.

Affected web-feature IDs:

Use case subdir: guides/security/security

Required files:

• Use case metadata (guide.md frontmatter)
• demo.html
• Use case guidance (guide.md)
• expectations.md
• tasks/task.md
• negative-demo.html
• grader.ts