load more button component and styling

[nielslyngsoe]

Implements a Tree Load More Button and restyles it to stand out clearly.

[Copilot]

Pull Request Overview

Introduces a specialized tree “Load more” button component and replaces inline uui-button instances with it, plus adds styling and localization.

• Swap out inline buttons for <umb-tree-load-more-button> in tree item and default tree components
• Add umb-tree-load-more-button element, its styles, and export entry
• Update localization files and core tree exports

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tree-item-base/tree-item-element-base.ts	Replaced inline uui-button with custom load-more component
core/tree/index.ts	Exported new components index
default/default-tree.element.ts	Replaced inline uui-button with custom load-more component
components/tree-load-more-button.element.ts	Added new load-more button component and styles
components/index.ts	Export entry for the new component
assets/lang/en.ts	Added loadMore translation
assets/lang/da.ts	Added loadMore translation

Comments suppressed due to low confidence (2)

src/Umbraco.Web.UI.Client/src/packages/core/tree/components/tree-load-more-button.element.ts:1

• [nitpick] No unit tests cover the new umb-tree-load-more-button component. Consider adding tests to verify rendering and click behavior.

import { css, customElement, html } from '@umbraco-cms/backoffice/external/lit';

src/Umbraco.Web.UI.Client/src/packages/core/tree/components/tree-load-more-button.element.ts:25

• The CSS variable name has an extra dash (--uui-size---uui-size-layout-3), which likely does not match the intended --uui-size-layout-3. Please correct the variable name.

			height: var(--uui-size---uui-size-layout-3);