- Refactor code to use idiomatic Kotlin functions like isNullOrEmpty(), associateBy, and appendRange

- Increase `DiffUtil` threshold in `CursorRecyclerAdapter` to 500 and optimize equality checks
- Simplify locale configuration by removing legacy Android SDK version checks
- Remove unnecessary `@SuppressLint` annotations and `@Volatile` modifiers
- Improve performance of collection operations in `ProductFragment` and `Preferences` using `associateBy` and `firstOrNull`
- Suppress deprecation warnings for `getOpacity` in `DrawableWrapper` and `TabsFragment`
- Clean up service binding logic in `Connection.kt` with better type casting

src/main/kotlin/com/michatec/store/utility/RxUtils.kt

@@ -12,7 +12,7 @@ import okhttp3.Response
 
 object RxUtils {
   private class ManagedDisposable(private val cancel: () -> Unit): Disposable {
-    @Volatile var disposed = false
+    var disposed = false
     override fun isDisposed(): Boolean = disposed
 
     override fun dispose() {