build(deps): bump @mdxeditor/editor from 3.55.0 to 4.2.1 (#11870)

Bumps [@mdxeditor/editor](https://github.com/mdx-editor/editor) from
3.55.0 to 4.2.1.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/mdx-editor/editor/releases">@​mdxeditor/editor's
releases</a>.</em></p>
<blockquote>
<h2>v4.2.1</h2>
<h2><a
href="https://github.com/mdx-editor/editor/compare/v4.2.0...v4.2.1">4.2.1</a>
(2026-08-21)</h2>
<h3>Bug Fixes</h3>
<ul>
<li>upgrade js-yaml to 4.3.1 to resolve GHSA-5p4m-2wfm-xmqj (<a
href="https://github.com/mdx-editor/editor/commit/3ff7296ffddcba1c60245c3ca27005b642f8b3c7">3ff7296</a>)</li>
</ul>
<h2>v4.2.0</h2>
<h1><a
href="https://github.com/mdx-editor/editor/compare/v4.1.1...v4.2.0">4.2.0</a>
(2026-08-02)</h1>
<h3>Bug Fixes</h3>
<ul>
<li>declare the frontmatter node as a block-level decorator (<a
href="https://github.com/mdx-editor/editor/commit/ebc4755212f643db5b6fb11d4e0418baad920200">ebc4755</a>),
closes <a
href="https://redirect.github.com/mdx-editor/editor/issues/957">#957</a></li>
<li>support links on selected images (<a
href="https://github.com/mdx-editor/editor/commit/d8c442b69fa030bac6e451447aa7a8510a6dec9a">d8c442b</a>),
closes <a
href="https://redirect.github.com/mdx-editor/editor/issues/753">#753</a></li>
</ul>
<h3>Features</h3>
<ul>
<li>mdxeditor-full-height opt-in class for editors that fill their
parent (<a
href="https://github.com/mdx-editor/editor/commit/cdeda5847e8d3ac319c1439fdfae3d8c2c93c2ef">cdeda58</a>),
closes <a
href="https://redirect.github.com/mdx-editor/editor/issues/953">#953</a></li>
</ul>
<h2>v4.1.1</h2>
<h2><a
href="https://github.com/mdx-editor/editor/compare/v4.1.0...v4.1.1">4.1.1</a>
(2026-07-29)</h2>
<h3>Bug Fixes</h3>
<ul>
<li>clear resolvable security audit findings in the dev dependency tree
(<a
href="https://github.com/mdx-editor/editor/commit/117dd849879b8917bfdb10d1d7cec709510b219c">117dd84</a>)</li>
<li>respect configured heading shortcuts (<a
href="https://github.com/mdx-editor/editor/commit/beacb4c3c21f572d34ec223dffcb1ec0be248771">beacb4c</a>)</li>
</ul>
<h2>v4.1.0</h2>
<h1><a
href="https://github.com/mdx-editor/editor/compare/v4.0.4...v4.1.0">4.1.0</a>
(2026-07-19)</h1>
<h3>Bug Fixes</h3>
<ul>
<li>harden Lexical adoption lifecycle edges (<a
href="https://github.com/mdx-editor/editor/commit/859bf459af165897652105e0aaa4f20fea0f162f">859bf45</a>)</li>
<li>pass Playwright install flags through npm (<a
href="https://github.com/mdx-editor/editor/commit/0b2d19b3bfffe2ffd2b98b9bb43820fb2148c0b4">0b2d19b</a>)</li>
<li>remove stray Realm provider token (<a
href="https://github.com/mdx-editor/editor/commit/c432da3a838fbc9ab4c1e09df892f10ce50e6e01">c432da3</a>)</li>
</ul>
<h3>Features</h3>
<ul>
<li>adopt Lexical 0.48 with compatibility gates (<a
href="https://github.com/mdx-editor/editor/commit/90a1466d5e675ffaca75b45a1cac75bcac222e09">90a1466</a>)</li>
<li>export Markdown from the active selection (<a
href="https://github.com/mdx-editor/editor/commit/a7c3baee1cced1307a17870e4524679e734039c2">a7c3bae</a>)</li>
<li>make search replacement state-backed (<a
href="https://github.com/mdx-editor/editor/commit/b108652c552920e88a1af55fe5c0b4fc220823f2">b108652</a>)</li>
</ul>
<h2>v4.0.4</h2>
<h2><a
href="https://github.com/mdx-editor/editor/compare/v4.0.3...v4.0.4">4.0.4</a>
(2026-06-18)</h2>
<!-- raw HTML omitted -->
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/mdx-editor/editor/commit/3ff7296ffddcba1c60245c3ca27005b642f8b3c7"><code>3ff7296</code></a>
fix: upgrade js-yaml to 4.3.1 to resolve GHSA-5p4m-2wfm-xmqj</li>
<li><a
href="https://github.com/mdx-editor/editor/commit/b5bc01b2c94c8a997238b89ced7ca9091e915454"><code>b5bc01b</code></a>
Merge pull request <a
href="https://redirect.github.com/mdx-editor/editor/issues/959">#959</a>
from alexander-neuschl-tu-dresden-de/patch-1</li>
<li><a
href="https://github.com/mdx-editor/editor/commit/b607c8ce2d88ce582ea933615dd8d67bb6dcbb8a"><code>b607c8c</code></a>
Update package-lock.json for js-yaml 4.3.1</li>
<li><a
href="https://github.com/mdx-editor/editor/commit/dda0c61c0b4f2aaea622b8c8017a68c491575ee7"><code>dda0c61</code></a>
Upgrade js-yaml to 4.3.1 to resolve high vulnerability</li>
<li><a
href="https://github.com/mdx-editor/editor/commit/d8c442b69fa030bac6e451447aa7a8510a6dec9a"><code>d8c442b</code></a>
fix: support links on selected images</li>
<li><a
href="https://github.com/mdx-editor/editor/commit/cdeda5847e8d3ac319c1439fdfae3d8c2c93c2ef"><code>cdeda58</code></a>
feat: mdxeditor-full-height opt-in class for editors that fill their
parent</li>
<li><a
href="https://github.com/mdx-editor/editor/commit/ebc4755212f643db5b6fb11d4e0418baad920200"><code>ebc4755</code></a>
fix: declare the frontmatter node as a block-level decorator</li>
<li><a
href="https://github.com/mdx-editor/editor/commit/117dd849879b8917bfdb10d1d7cec709510b219c"><code>117dd84</code></a>
fix: clear resolvable security audit findings in the dev dependency
tree</li>
<li><a
href="https://github.com/mdx-editor/editor/commit/88b7545e5d7095d526eb1c79e660db157848e583"><code>88b7545</code></a>
Merge branch 'pr-954'</li>
<li><a
href="https://github.com/mdx-editor/editor/commit/2b1af77dffc69806d94c8b72c9d1e8fd3e4f99cd"><code>2b1af77</code></a>
Merge pull request <a
href="https://redirect.github.com/mdx-editor/editor/issues/952">#952</a>
from 11suixing11/fix/allowed-heading-shortcuts</li>
<li>Additional commits viewable in <a
href="https://github.com/mdx-editor/editor/compare/v3.55.0...v4.2.1">compare
view</a></li>
</ul>
</details>
<br />

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ui/package.json

@@ -34,7 +34,7 @@
     "@dnd-kit/sortable": "^10.0.0",
     "@dnd-kit/utilities": "^3.2.2",
     "@lexical/link": "0.49.0",
-    "@mdxeditor/editor": "^3.55.0",
+    "@mdxeditor/editor": "^4.2.1",
     "@paperclipai/adapter-claude-local": "workspace:*",
     "@paperclipai/adapter-codex-local": "workspace:*",
     "@paperclipai/adapter-cursor-cloud": "workspace:*",