Refactor Backdrop <3

tools/kawarp-build/stubs/androidx/compose/runtime/MutableIntState.java

@@ -0,0 +1,5 @@
+package androidx.compose.runtime;
+public interface MutableIntState extends State {
+    int getIntValue();
+    void setIntValue(int value);
+}

tools/kawarp-build/stubs/androidx/compose/runtime/SnapshotIntStateKt.java

@@ -0,0 +1,4 @@
+package androidx.compose.runtime;
+public final class SnapshotIntStateKt {
+    public static MutableIntState mutableIntStateOf(int value) { return null; }
+}