Adding Lychee Config files

[eshanrnh]

📋 Description

Adding Lychee to check for broken links in incoming PRs.

To test:

1. Run the choco install lychee command on Windows PowerShell to install Lychee. You might want to check the command for the Linux machine.
2. Verify install using lychee --version.
3. Go to the local UmbracoDocs repo.
4. Add a Lychee config file in .github/lychee.toml.
5. Add .lycheeignore at the repo root.
6. Test Lychee locally. From the repo root, run: lychee --config .github/lychee.toml --format json --output lychee_output_cm.json "16/umbraco-cms/**/*.md".
7. To export to Excel:

$json = Get-Content lychee_output_cm.json | ConvertFrom-Json

# Function to flatten a map
function Flatten-Map($map, $statusType) {
    $list = @()
    foreach ($file in $map.PSObject.Properties.Name) {
        foreach ($link in $map.$file) {
            $list += [PSCustomObject]@{
                file         = $file
                url          = $link.url
                status       = $statusType
                redirect_url = if ($link.PSObject.Properties.Match('redirect_url')) { $link.redirect_url } else { $null }
                line         = if ($link.PSObject.Properties.Match('line')) { $link.line } else { $null }
                reason       = if ($link.PSObject.Properties.Match('reason')) { $link.reason } else { $null }
            }
        }
    }
    return $list
}

# Flatten each map
$success = Flatten-Map $json.success_map 'Success'
$errors  = Flatten-Map $json.error_map 'Error'
$excluded = Flatten-Map $json.excluded_map 'Excluded'

# Combine all
$allLinks = $success + $errors + $excluded

# Export to CSV
$allLinks | Export-Csv -Path lychee_links_cms.csv -NoTypeInformation

8. The other 2 config files are for GitHub Actions. If you want to test, add those files to:

• .github/lychee.toml
• .github/workflows/check-broken-pr-links.yml

9. Create a PR with the following use cases. If there are broken links, a comment should appear from [github-actions] listing the broken links, and the workflow should fail.

• Clean file without broken links
• File with broken internal or external links
• File has only internal anchors
• Redirects (301/302)
• Any other

📎 Related Issues (if applicable)

✅ Contributor Checklist

I've followed the Umbraco Documentation Style Guide and can confirm that:

• Code blocks are correctly formatted.
• Sentences are short and clear (preferably under 25 words).
• Passive voice and first-person language (“we”, “I”) are avoided.
• Relevant pages are linked.
• All links work and point to the correct resources.
• Screenshots or diagrams are included if useful.
• Any code examples or instructions have been tested.
• Typos, broken links, and broken images are fixed.

Product & Version (if relevant)

Deadline (if relevant)

Anytime

📚 Helpful Resources

• 🧾 Umbraco Contribution Guidelines
• ✍️ Umbraco Documentation Style Guide

[sofietoft]

So great to have a rule that checks for broken links!
I'm very excited to see how this will help us out 💪

I've made some suggestions to the YAML file.
See how a comment looks with the suggested changes here: sofietoft#91 (comment)

[eshanrnh]

Thank you for testing it out and adding your suggestions, @sofietoft 🙌 The output message definitely looks fantastic, it's well-spaced and easy to read 💪

I've incorporated all your suggestions.

[sofietoft]

Perfect! Let's get this merged, so we can start informing contributors about potential broken links in their PRs 👏