Make `code-tools` in or under "Other formats"

It was discussed somewhere but cannot find it again.
With the manuscript project type and "other formats" linking, it feels code-tools makes less sense in terms of purposes and aesthetics/design.

I am here suggesting to (either or both):

1. move code-tools in a "section" such as "Other formats".
2. Make a "Quarto" format which would "link" the source code.

The main reason is that code-tools is less visible and not really pretty with the margin/sidebar.

---
title: "Quarto Playground"
format:
  html: default
  pdf: default
toc: true
code-tools: true
---

This is a playground for Quarto.

## Section 1

{{< lipsum 1 >}}

## Section 2

{{< lipsum 1 >}}

No implementation files or tests are named. Start by locating the code-tools placement and format-linking entry points in the Quarto CLI, then compare the rendered layout with the attached example. Done means an agreed approach is implemented and the resulting code-tools or Quarto format presentation is verified.