Feature: Add Adaptive Layout / Large Screen support

[github-actions]

Summary

The app currently has no adaptive layout support for large screens (tablets, foldables, desktops). Jetpack Compose provides WindowSizeClass and adaptive layout libraries specifically for this. Adding a demo would significantly improve the showcase value of this cookbook.

Description

Android now requires apps targeting large screens to follow large screen quality guidelines. The Compose toolkit provides:

• WindowSizeClass (from androidx.compose.material3:material3-window-size-class) — already in Dependencies.kt.
• androidx.compose.material3.adaptive — new adaptive navigation and scaffold APIs.
• NavigationSuiteScaffold — automatically switches between NavigationBar, NavigationRail, and NavigationDrawer based on window size.

Proposed Demo

A demo screen that shows:

1. Adaptive navigation using NavigationSuiteScaffold — bottom bar on compact, rail on medium, drawer on expanded.
2. Two-pane layout using ListDetailPaneScaffold from androidx.compose.material3.adaptive.layout.
3. Sample: a list of items on the left pane, detail view on the right pane when screen is large enough.

Proposed Changes

1. Add androidx.compose.material3:material3-adaptive-navigation-suite to Dependencies.kt.
2. Create a new demo module or screen demos/adaptive/.
3. Update app/build.gradle.kts and navigation to include the adaptive demo.
4. Update README to document the new demo.

Acceptance Criteria

• NavigationSuiteScaffold switches navigation component based on WindowSizeClass.
• ListDetailPaneScaffold shows a two-pane layout on tablets.
• Works on phone (single pane), tablet (two pane), and foldable (hinge-aware).
• Supports dark mode.

References

• Adaptive layouts in Compose
• NavigationSuiteScaffold
• ListDetailPaneScaffold