[WIP] Fix type safety issues in bullet and task list parsing

[Copilot]

Thanks for the feedback on #7178. I've created this new PR, which merges into #7178, to address your comment. I will work on the changes and keep this PR's description up to date as I make progress.

Original PR: #7178
Triggering review: #7178 (review)

LGTM but I'd have a look at @copilot 's suggestions, especially the ones that refer to type safety.

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[changeset-bot]

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Latest commit: 42ddd02

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