To make the main screen less cluttered and easier to navigate, the demo activities have been grouped into a list. This provides a cleaner and more organized user experience.

This change also pulls in Material 3.

This commit updates the main screen to use a Material 3 Scaffold, providing a more modern and consistent layout. The TopAppBar has also been updated to be center-aligned.

Refactored the demo list screen to support internationalization by extracting all hardcoded strings into `strings.xml`. The `Activity` and `ActivityGroup` data classes were updated to use `@StringRes` integer IDs instead of `String` literals.

Additionally, the `DemoList` composable has been broken down into smaller, more focused composables (`GroupHeaderItem` and `DemoActivityItem`) to improve readability and maintainability.

This commit introduces a new example activity, `TileOverlayActivity`, to demonstrate the usage and dynamic updating of the `TileOverlay` composable.

The demo showcases:
- Providing custom tiles using a `TileProvider`.
- Refreshing tile content by calling `clearTileCache()` on the `TileOverlayState`. The example updates tiles every second to display an incrementing number.
- Replacing the `TileProvider` instance to trigger a full refresh of the overlay.

The new activity is registered in the manifest and is accessible from the main screen of the demo application.

The TileOverlayActivity was previously launched from a standalone button in MainActivity. This commit moves it into the "Map Features" group within Demo.kt, ensuring a more consistent and organized user experience.

This change also removes the now-redundant button from MainActivity.

…-state

…-state

…better demonstrate how to update a `TileOverlay`.

The `LaunchedEffect` in `TileOverlayDemo` now includes comments explaining two distinct update strategies:

1.  **Cache Invalidation**: Calling `state.clearTileCache()` to force a redraw of tiles using the existing `TileProvider`.
2.  **Provider Replacement**: Creating a new `TileProvider` instance, which triggers a full replacement of the overlay's data source.