fix: resolve emulator crash - thread safety and icon fallback

- NativeSearch: move onResult/onError callbacks outside withContext(Dispatchers.IO) to prevent CalledFromWrongThreadException
- SearchStrategy: change callback types to suspend to enable proper coroutine chaining
- SearchCoordinator: remove leaked CoroutineScope, rely on suspend callback chaining for fallback flow
- Resources: add mipmap-hdpi/mdpi/xhdpi/xxhdpi icon fallbacks for API < 26 devices

build.gradle.kts

@@ -0,0 +1,5 @@
+plugins {
+    id("com.android.application") version "8.2.0" apply false
+    id("org.jetbrains.kotlin.android") version "1.9.20" apply false
+    id("com.google.devtools.ksp") version "1.9.20-1.0.14" apply false
+}