init: android project scaffold (Phase 28.1)

- Kotlin DSL build with version catalog (AGP 8.7, Kotlin 2.1, Compose BOM 2025.01)
- app module: Compose + Material 3, dark theme, network security config
- DualNetworkTestScreen — Phase 28.1 gate screen (buttons wired in 28.1.2)
- YarisApp, MainActivity, YarisOBDTheme
- ProGuard rules for Retrofit/OkHttp/Kotlinx Serialization/Coil/MapLibre/Room
- cleartext allowed for 10.42.0.1 + yaris.local
- gradle wrapper properties (needs Android Studio to generate wrapper jar)

android/.gitignore

@@ -0,0 +1,12 @@
+# Android project ignores
+*.iml
+.gradle/
+build/
+local.properties
+.idea/
+*.apk
+*.aab
+*.jks
+*.keystore
+!gradle/wrapper/gradle-wrapper.jar
+!gradle/wrapper/gradle-wrapper.properties