address feedback: focus detail screens anywhere in the stack, brighter sheet

- navigateDetail scans the whole back stack and pops back to a matching album/artist/
  playlist, not just the top, so artist -> album -> now playing -> view artist focuses the
  existing artist instead of pushing a second one
- raise the sheet container to surfaceContainerHigh so it reads against the background
  behind it

app/src/main/kotlin/com/subtracks/ui/AppRoot.kt

@@ -52,6 +52,7 @@ import androidx.lifecycle.ViewModelStoreOwner
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import androidx.lifecycle.viewModelScope
 import androidx.lifecycle.viewmodel.compose.LocalViewModelStoreOwner
+import androidx.navigation.NavBackStackEntry
 import androidx.navigation.NavType
 import androidx.navigation.compose.NavHost
 import androidx.navigation.compose.composable
@@ -187,9 +188,18 @@ private fun MainNavigation() {
         value: String,
         route: String,
     ) {
-        val top = navController.currentBackStackEntry
-        if (top?.destination?.route == pattern && top.arguments?.getString(argument) == value) return
-        navController.navigate(route)
+        val matches: (NavBackStackEntry?) -> Boolean = { entry ->
+            entry?.destination?.route == pattern && entry.arguments?.getString(argument) == value
+        }
+        if (matches(navController.currentBackStackEntry)) return
+        if (navController.currentBackStack.value.none(matches)) {
+            navController.navigate(route)
+            return
+        }
+        var guard = navController.currentBackStack.value.size
+        while (guard-- > 0 && !matches(navController.currentBackStackEntry) && navController.popBackStack()) {
+            // pop until the matching entry is back on top
+        }
     }
     LaunchedEffect(Unit) { playbackController.connect() }
     LaunchedEffect(Unit) { if (nowPlayingOpen) nowPlayingProgress = 1f }

app/src/main/kotlin/com/subtracks/ui/components/ItemContextMenu.kt

@@ -141,6 +141,7 @@ fun ItemContextMenu(
         onDismissRequest = { dismiss() },
         sheetState = sheetState,
         dragHandle = null,
+        containerColor = MaterialTheme.colorScheme.surfaceContainerHigh,
     ) {
         MenuHeader(target)
         when (target) {

app/src/main/kotlin/com/subtracks/ui/library/LibraryScreen.kt

@@ -528,6 +528,7 @@ fun LibraryScreen(
         ModalBottomSheet(
             onDismissRequest = { showOptions = false },
             dragHandle = null,
+            containerColor = MaterialTheme.colorScheme.surfaceContainerHigh,
         ) {
             ListOptionsSheet(
                 listQuery = listQuery,