refs TryGhost/Team#3147
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### <samp>🤖 Generated by Copilot at 7dfd8bf</samp>
This file adds a function to clean and format the HTML of the
`koenig-lexical-editor-input` component and passes it to the
`HtmlOutputPlugin` component.
refs TryGhost/Team#3008
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### <samp>🤖 Generated by Copilot at 2a60623</samp>
This pull request adds a new experimental feature for displaying an
announcement bar at the top of the site. It introduces a new component
template and class for the announcement bar, a new feature flag and its
UI controls, and some CSS adjustments for the editor input and the
announcement bar.
refs TryGhost/Team#3008
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### <samp>🤖 Generated by Copilot at f785fd8</samp>
This change adds a new component `koenig-lexical-editor-input` that
renders a React component using the `@tryghost/koenig-lexical` package,
which provides a new editor for Ghost that supports rich text and
markdown editing. The component can be used to edit HTML content using
the Lexical editor, and syncs the HTML content with the `html` argument
and the `onChangeHtml` callback. The component also handles dynamic
import, loading, error, and dark mode scenarios.
