docs: a new guide on overriding LyoD output

[berezovskyi]

Extracted from oslc-op/refimpl#27

[Copilot]

Pull Request Overview

Adds a new documentation guide for customizing Lyo Designer’s REST responses and updates the site navigation to include an "Advanced topics" section.

• Introduces a new markdown page with tips, options, and a sample interceptor for overriding generated responses.
• Updates mkdocs.yml to add an "Advanced topics" nav entry pointing to the new guide.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
mkdocs.yml	Added "Advanced topics" group and link to the new guide
docs-new/eclipse_lyo/designer/advanced/manipulating-responses.md	Created guide on overriding Lyo Designer output with examples

Comments suppressed due to low confidence (1)

mkdocs.yml:196

• The nav entry path doesn’t match the new file location under docs-new/. Either move the file into the docs folder structure or update this path so mkdocs can find the page.

        - Overriding Lyo Designer output: eclipse_lyo/designer/advanced/manipulating-responses.md