docs(examples): add overview and clarify npm packaging

[kmbroai]

Summary

Add an overview for the repository examples and document that they are not shipped in the npm package.

Changes

• Add examples/README.md with links to the findings CSV template and custom validation demo.
• Explain that the top-level examples are repository-only, while the bundled plugin's own example artifacts remain packaged.
• Keep the existing package configuration unchanged: the package lives in sdk/typescript, its files list excludes the top-level examples, and the existing package checker rejects unexpected files.

Testing

• Prettier check of examples/README.md: passed.
• Checked every relative link in the new README: passed.
• pnpm pack --pack-destination ../../dist (including the TypeScript build): passed.
• node scripts/check-package.mjs ../../dist/openai-codex-security-0.1.20.tgz plugin-files.json: passed, validating 269 archive entries.
• Inspected the generated tarball: no top-level repository examples or examples README; all four bundled plugin example artifacts remain present.
• git diff --check origin/main...HEAD: passed.
• Full unit tests and installed-package smoke tests were not run because this change only adds documentation.

Risk and rollout

Low risk. Documentation only; no CLI, runtime, dependency, or package configuration changes. No rollout steps are required.

Public disclosure review

• No customer, partner, prospect, or user identities, data, or identifying details are included.
• No credentials, personal data, private source, scan findings, or nonpublic links or tickets are included.
• I reviewed the branch name, title, description, commits, changes, comments, logs, screenshots, attachments, and links for public disclosure.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
🔒 Security Review	✅ Completed 2026-08-25T22:28:21.647354Z	a6cd1bc	PR opened

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