feat(phone-app): setup Jetpack Compose BOM, Kotlin Compose compiler, and Material 3 theme

[hungify]

What to build

Configure the Modern Android Jetpack Compose stack and build the Material 3 design foundation for the phone-app module.

Acceptance criteria

• Add Kotlin Compose compiler plugin (org.jetbrains.kotlin.plugin.compose) matching Kotlin 2.0+ in libs.versions.toml and build.gradle.kts.
• Add Compose BOM (androidx.compose:compose-bom), Compose UI, Material 3 (androidx.compose.material3:material3), Material Icons Extended, androidx.activity:activity-compose, and androidx.lifecycle:lifecycle-runtime-compose.
• Enable buildFeatures { compose = true } in phone-app/app/build.gradle.kts.
• Create Material 3 theme foundation (Color.kt, Type.kt, Theme.kt) with Dynamic Color support on Android 12+ (dynamicLightColorScheme / dynamicDarkColorScheme) and Dark/Light theme switching.
• Unit tests and build verification pass cleanly (./gradlew testDebugUnitTest).

Blocked by

• None (can start immediately)

[hungify]

Completed in 389ad80: configured Jetpack Compose BOM, Kotlin Compose compiler plugin, and Material 3 theme with Dynamic Color support.