Full Compose settings (#8201)

* Uses Voyager for navigation.
* Replaces every screen inside settings except category editor screen since it's
called from several places.

app/src/main/java/eu/kanade/presentation/util/LazyListState.kt

@@ -8,6 +8,16 @@ import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
 
+@Composable
+fun LazyListState.isScrolledToStart(): Boolean {
+    return remember {
+        derivedStateOf {
+            val firstItem = layoutInfo.visibleItemsInfo.firstOrNull()
+            firstItem == null || firstItem.offset == layoutInfo.viewportStartOffset
+        }
+    }.value
+}
+
 @Composable
 fun LazyListState.isScrolledToEnd(): Boolean {
     return remember {

app/src/main/java/eu/kanade/presentation/util/Navigator.kt

@@ -0,0 +1,15 @@
+package eu.kanade.presentation.util
+
+import androidx.compose.runtime.ProvidableCompositionLocal
+import androidx.compose.runtime.staticCompositionLocalOf
+import com.bluelinelabs.conductor.Router
+
+/**
+ * For interop with Conductor
+ */
+val LocalRouter: ProvidableCompositionLocal<Router?> = staticCompositionLocalOf { null }
+
+/**
+ * For invoking back press to the parent activity
+ */
+val LocalBackPress: ProvidableCompositionLocal<(() -> Unit)?> = staticCompositionLocalOf { null }

app/src/main/java/eu/kanade/presentation/util/Preference.kt

@@ -0,0 +1,13 @@
+package eu.kanade.presentation.util
+
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.State
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.remember
+import eu.kanade.tachiyomi.core.preference.Preference
+
+@Composable
+fun <T> Preference<T>.collectAsState(): State<T> {
+    val flow = remember(this) { changes() }
+    return flow.collectAsState(initial = get())
+}