Changelog

Unreleased

Breaking: directives, the opaque carry among them (now carry), are spelled under an !adf: prefix (!adf:name … !adf:/name, !adf:name[content]{attrs}, !adf:name arg {attrs}) in place of the :::/::/:name forms: text holding an unescaped !adf: is claimed, and adf is an ordinary code block language. Convert stored markdown per MIGRATION.md.
Breaking: unspellable-link leaves ConvertErrorCode; a link whose href or title no CommonMark escape spells is written as !adf:link[text]{attrs}.
Breaking: some directive refusals carry malformed-directive where they carried unsupported-node-shape, and an empty node's leaf and closed spellings swap which one parses; MIGRATION.md lists each.
Breaking: a link whose text holds another link keeps the inner link and leaves the outer brackets literal text, where 0.1.0 split the outer link around it; see MIGRATION.md.
Add adfToPlainMarkdown and plainMarkdownToAdf, a lossy pair converting ADF to and from markdown GitHub, GitLab and Obsidian render: alerts, callouts, task lists, ==highlights== and pipe tables.
Spell rule's color, style and weight, layoutSection's columnRuleStyle and a link's collection, id and occurrenceKey directly where they rode the opaque carry.
Fix an image inside another image's description: it flattens into the alt text, where it was refused.

First release: lossless conversion between ADF and an extended markdown flavour — adfToMarkdown, markdownToAdf and isAdfDocument. Nothing throws, and every error carries a code from a closed list.