Fix/cdn app generation

[godronus]

No description provided.

[Copilot]

Pull request overview

This PR improves the repo’s “pipeline source contract” hygiene by adding automation to keep Copilot instructions and the manifest in sync, and updates a few CDN examples/documentation to better reflect current behavior.

Changes:

• Extend check-copilot-sync.sh with an advisory check that warns when example projects exist on disk but aren’t tracked in manifest.json.
• Fix CDN example response-body replacement to use the incoming body_size when calling set_http_response_body.
• Add a PR-triggered GitHub Actions workflow to run the sync check, and add initial .github/copilot-instructions.md.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
fastedge-plugin-source/check-copilot-sync.sh	Adds “example directories tracked in manifest” advisory check and tightens doc-path matching logic.
examples/cdn/md2html/src/lib.rs	Uses body_size when replacing the full response body.
examples/cdn/custom_error_pages/src/lib.rs	Uses body_size when replacing the full response body; updates callback param name.
examples/cdn/cors/src/lib.rs	Updates module-level configuration docs to clarify dormant behavior when unset.
.github/workflows/copilot-sync.yml	Adds a workflow to run the sync checker on relevant PR changes.
.github/copilot-instructions.md	Introduces repo-specific PR review instructions and a mapping table for generated docs.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.