Co-authored-by: Christophe Dervieux <[email protected]>

closes #127

Example that uses uv for Python package management.

actions/checkout@v6 moved credentials from .git/config to a separate file
using includeIf for security (actions/checkout#2286). This breaks quarto
publish gh-pages which uses git worktrees, since the includeIf condition
doesn't match worktree paths.

The fix propagates the credential configuration to worktrees by adding a
second includeIf rule that matches .git/worktrees/* paths. This is backward
compatible - it only runs if v6-style credentials exist.

Also updates test.yaml to use checkout@v6 and documents v6 compatibility
in publish/README.md.

Creates a test workflow that generates a documentation website from the
repository READMEs and publishes it to gh-pages. This tests the full
publish action workflow including the worktree credential handling.

The workflow:
- Runs on push to main and manual dispatch
- Dynamically generates Quarto site from READMEs via heredoc
- Fixes relative links to work in the rendered site
- Publishes to gh-pages, testing the complete worktree code path

Also creates a minimal documentation site at quarto-dev.github.io/quarto-actions/
as a useful side benefit.

Uses yq to dynamically discover and add all example-*.md files to a
floating sidebar. Automatically adapts to new examples without manual
config updates.