Improve detecting which items should be reconverted when using skip-level lists

[mmotyczynska]

🚀 Summary

A brief summary of what this PR changes.

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📌 Related issues

• Closes https://github.com/ckeditor/ckeditor5-commercial/issues/9765
• Closes https://github.com/ckeditor/ckeditor5-commercial/issues/9764
• Closes https://github.com/ckeditor/ckeditor5-commercial/issues/9766
• Closes https://github.com/ckeditor/ckeditor5-commercial/issues/9761

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💡 Additional information

Optional: Notes on decisions, edge cases, or anything helpful for reviewers.

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🧾 Checklists

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Author checklist

• Is the changelog entry intentionally omitted?
• Is the change backward-compatible?
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• Does this change affect any of the above?
• Is performance impacted?
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• Have tests been added that fail without this change (against regression)?
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• Are there any changes the team should be informed about (e.g. architectural, difficult to revert in future versions or having impact on other features)?
• Were these changes documented (in Logbook)?

Reviewer checklist

• PR description explains the changes and the chosen approach (especially when performance, API, or UX is affected).
• The changelog entry is clear, user‑ or integrator-facing, and it describes any breaking changes.
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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

Missing listIndent override in skip-level stack entries

Medium Severity

The synthetic modelAttributes for skip-level gap entries override listItemId to list-item-skip-${i} but do not override listIndent. When the fallback path is used (referenceItem is node at itemIndent), the listIndent retains itemIndent instead of i. The checkAttributes:list handler compares viewElement.id against getViewElementIdForListType(modelAttributes.listType, modelAttributes.listIndent), generating the wrong expected ID (e.g., list-numbered-2 instead of list-numbered-1). This causes a permanent false-positive mismatch, triggering unnecessary reconversion of skip-level items on every model change.

 

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