feat(android): seed headers on detail-screen Loading state (audit v3 Bug-8)

AlbumDetail / ArtistDetail / PlaylistDetail previously rendered only
the AppBar title from the navigation seed during Loading, with a bare
skeleton body. Now each Loading branch renders the full header from
the seed when present — cover + title + artist/description + count —
above the skeleton track rows / album grid, so the screen reads as
itself instantly instead of skeleton-then-pop. Falls back to the
plain skeleton when no seed (e.g. deep links, track-row navigations
that only carry an id).

Action buttons (Play / Shuffle / Like / Regenerate) are intentionally
omitted from the seeded header — they need the loaded track list.

Added @file:Suppress(TooManyFunctions) to AlbumDetailScreen (now at
the 11-function cap with the new SeededAlbumLoading helper).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

android/app/src/main/java/com/fabledsword/minstrel/library/ui/AlbumDetailScreen.kt

@@ -1,3 +1,5 @@
+@file:Suppress("TooManyFunctions") // Compose screen + private helper composables
+
 package com.fabledsword.minstrel.library.ui
 
 import androidx.compose.foundation.background
@@ -120,7 +122,8 @@ private fun AlbumDetailStateContent(
 ) {
     Crossfade(targetState = state, label = "album-detail") { s ->
         when (s) {
-            is AlbumDetailUiState.Loading -> SkeletonTrackList()
+            is AlbumDetailUiState.Loading ->
+                if (s.seed != null) SeededAlbumLoading(s.seed) else SkeletonTrackList()
             is AlbumDetailUiState.Error -> EmptyState(
                 title = "Couldn't load album",
                 body = s.message,
@@ -370,6 +373,53 @@ private fun SkeletonTrackList() {
     }
 }
 
+/**
+ * Loading body that renders the album header from the navigation seed
+ * (cover + title + artist + count) so the screen reads as itself
+ * immediately, with skeleton track rows below until the fetch lands.
+ * Action buttons are omitted — they need the real track list.
+ */
+@Composable
+private fun SeededAlbumLoading(seed: AlbumRef) {
+    LazyColumn(modifier = Modifier.fillMaxSize()) {
+        item {
+            Row(
+                modifier = Modifier.fillMaxWidth().padding(16.dp),
+                horizontalArrangement = Arrangement.spacedBy(16.dp),
+                verticalAlignment = Alignment.CenterVertically,
+            ) {
+                AlbumCover(seed)
+                Column(modifier = Modifier.weight(1f)) {
+                    Text(
+                        text = seed.title,
+                        style = MaterialTheme.typography.headlineSmall,
+                        color = MaterialTheme.colorScheme.onBackground,
+                        maxLines = 2,
+                        overflow = TextOverflow.Ellipsis,
+                    )
+                    if (seed.artistName.isNotEmpty()) {
+                        Text(
+                            text = seed.artistName,
+                            style = MaterialTheme.typography.bodyMedium,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant,
+                            maxLines = 1,
+                            overflow = TextOverflow.Ellipsis,
+                        )
+                    }
+                    Spacer(Modifier.height(4.dp))
+                    Text(
+                        text = trackCountLine(seed),
+                        style = MaterialTheme.typography.bodySmall,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                    )
+                }
+            }
+        }
+        item { HorizontalDivider() }
+        items(SKELETON_TRACK_ROWS) { SkeletonTrackRow() }
+    }
+}
+
 private const val SECONDS_PER_MINUTE = 60
 
 private fun formatDuration(seconds: Int): String {

android/app/src/main/java/com/fabledsword/minstrel/library/ui/ArtistDetailScreen.kt

@@ -89,7 +89,12 @@ fun ArtistDetailScreen(
         ) {
             Crossfade(targetState = state, label = "artist-detail") { s ->
                 when (s) {
-                    is ArtistDetailUiState.Loading -> SkeletonArtistAlbumsGrid()
+                    is ArtistDetailUiState.Loading ->
+                        if (s.seed != null) {
+                            SeededArtistLoading(s.seed)
+                        } else {
+                            SkeletonArtistAlbumsGrid()
+                        }
                     is ArtistDetailUiState.Error -> EmptyState(
                         title = "Couldn't load artist",
                         body = s.message,
@@ -258,3 +263,47 @@ private fun SkeletonArtistAlbumsGrid() {
         items(SKELETON_ARTIST_GRID_TILES) { SkeletonAlbumTile() }
     }
 }
+
+/**
+ * Loading body that renders the artist header from the navigation
+ * seed (avatar + name + album count) with a skeleton album grid
+ * below until the fetch lands. Play / Like omitted — they need the
+ * loaded detail.
+ */
+@Composable
+private fun SeededArtistLoading(seed: ArtistRef) {
+    LazyVerticalGrid(
+        columns = GridCells.Adaptive(minSize = 176.dp),
+        contentPadding = PaddingValues(8.dp),
+        verticalArrangement = Arrangement.spacedBy(8.dp),
+        horizontalArrangement = Arrangement.spacedBy(8.dp),
+        modifier = Modifier.fillMaxSize(),
+    ) {
+        item(span = { GridItemSpan(maxLineSpan) }) {
+            Row(
+                modifier = Modifier.fillMaxWidth().padding(8.dp),
+                verticalAlignment = Alignment.CenterVertically,
+                horizontalArrangement = Arrangement.spacedBy(12.dp),
+            ) {
+                ArtistAvatar(seed)
+                Column(modifier = Modifier.weight(1f)) {
+                    Text(
+                        text = seed.name,
+                        style = MaterialTheme.typography.headlineSmall,
+                        color = MaterialTheme.colorScheme.onBackground,
+                        maxLines = 2,
+                        overflow = TextOverflow.Ellipsis,
+                    )
+                    if (seed.albumCount > 0) {
+                        Text(
+                            text = albumCountLine(seed),
+                            style = MaterialTheme.typography.bodySmall,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant,
+                        )
+                    }
+                }
+            }
+        }
+        items(SKELETON_ARTIST_GRID_TILES) { SkeletonAlbumTile() }
+    }
+}

android/app/src/main/java/com/fabledsword/minstrel/playlists/ui/PlaylistDetailScreen.kt

@@ -299,7 +299,8 @@ private fun PlaylistDetailContent(
     navController: NavHostController,
 ) {
     Crossfade(targetState = state, label = "playlist-detail") { s -> when (s) {
-        is PlaylistDetailUiState.Loading -> SkeletonPlaylistTrackList()
+        is PlaylistDetailUiState.Loading ->
+            s.seed?.let { SeededPlaylistLoading(it) } ?: SkeletonPlaylistTrackList()
         is PlaylistDetailUiState.Error -> ErrorBlock(s.message, viewModel::refresh)
         is PlaylistDetailUiState.Success -> {
             val likedTrackIds by viewModel.likedTrackIds.collectAsState()
@@ -553,6 +554,53 @@ private fun SkeletonPlaylistTrackList() {
     }
 }
 
+/**
+ * Loading body that renders the playlist header from the navigation
+ * seed (cover + name + description + count) with skeleton track rows
+ * below. Play / Shuffle / Regenerate omitted — they need the loaded
+ * track list.
+ */
+@Composable
+private fun SeededPlaylistLoading(seed: PlaylistRef) {
+    LazyColumn(modifier = Modifier.fillMaxSize()) {
+        item {
+            Row(
+                modifier = Modifier.fillMaxWidth().padding(16.dp),
+                horizontalArrangement = Arrangement.spacedBy(16.dp),
+                verticalAlignment = Alignment.CenterVertically,
+            ) {
+                PlaylistCover(seed)
+                Column(modifier = Modifier.weight(1f)) {
+                    Text(
+                        text = seed.name,
+                        style = MaterialTheme.typography.headlineSmall,
+                        color = MaterialTheme.colorScheme.onBackground,
+                        maxLines = 2,
+                        overflow = TextOverflow.Ellipsis,
+                    )
+                    if (seed.description.isNotEmpty()) {
+                        Text(
+                            text = seed.description,
+                            style = MaterialTheme.typography.bodyMedium,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant,
+                            maxLines = 3,
+                            overflow = TextOverflow.Ellipsis,
+                        )
+                    }
+                    Spacer(Modifier.height(4.dp))
+                    Text(
+                        text = "${seed.trackCount} tracks",
+                        style = MaterialTheme.typography.bodySmall,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                    )
+                }
+            }
+        }
+        item { HorizontalDivider() }
+        items(SKELETON_PLAYLIST_ROWS) { SkeletonTrackRow() }
+    }
+}
+
 @Composable
 private fun ErrorBlock(message: String, onRetry: () -> Unit) {
     var retried by remember { mutableStateOf(false) }