feat: add md-carousel component

[treeder]

Adds the Material 3 image carousel component. Includes the md-carousel and md-carousel-item wrappers, powered by standard native CSS Scroll Snapping (scroll-snap-type / scroll-snap-align) and Lit properties, properly exposed in the module root aliases.

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PR created automatically by Jules for task 15402652083068191811 started by @treeder

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[gemini-code-assist]

Code Review

This pull request introduces a new Carousel component, including md-carousel and md-carousel-item elements, with support for horizontal scrolling and scroll snapping. The feedback suggests several improvements for better maintainability and accessibility: removing empty constructors and properties to reduce boilerplate, using CSS custom properties for gap and padding to allow for easier theming, and implementing an ariaLabel property to support localized labels. Additionally, it is recommended to reorder the imports in all.js to keep them grouped by component type.

[gemini-code-assist]

The imports for the carousel component are currently interspersed with the button component imports (e.g., between button.js and filled-tonal-button.js). It is recommended to group imports by component type to maintain a clean and organized structure. Consider moving these imports after the complete buttons group.

[gemini-code-assist]

The static properties object and the constructor are currently empty and do not contain any logic. They can be removed to simplify the component definition and reduce boilerplate.

[gemini-code-assist]

The empty constructor can be removed. Additionally, consider adding an ariaLabel property to allow users to provide a localized or custom label for the carousel, which is important for accessibility and internationalization.

  static properties = {
    /**
     * The aria-label of the carousel.
     */
    ariaLabel: {attribute: 'aria-label'},
  };

  ariaLabel = 'Carousel';

[gemini-code-assist]

Use the ariaLabel property to set the aria-label attribute on the internal carousel container. This allows the component to support dynamic and localized labels instead of a hardcoded string.

Suggested change

	<div class="carousel" role="list" aria-label="Carousel">
	<div class="carousel" role="list" aria-label=${this.ariaLabel || 'Carousel'}>

[gemini-code-assist]

Using hardcoded values for gap and padding limits the flexibility of the component. It is better to use CSS custom properties to allow for easier theming and consistency with other Material components in the project.

Suggested change

	gap: 8px; /* Optional gap */
	padding: 16px;
	gap: var(--md-carousel-gap, 8px);
	padding: var(--md-carousel-padding, 16px);